Keyword: electron
Paper Title Other Keywords Page
MOPLXGD2 Progress Towards Demonstration of a Plasma-Based FEL plasma, FEL, laser, wakefield 6
 
  • E. Chiadroni
    LNF-INFN, Frascati, Italy
 
  Plasma-based technology promises a revolution in the field of particle accelerators by pushing beams to gigaelectronvolt energies within centimeter distances. Several experiments are ongoing world-wide towards demonstration of a plasma based FEL enabling the realization of ultra-compact facilities for user applications like Free-Electron Lasers (FEL). The progress towards a plasma based FEL user facility is here reported, with particular focus on the recent results about the first experimental evidence of FEL lasing by a compact (3 cm) particle beam-driven plasma accelerator at the SPARC_LAB test facility. The status and prospects are discussed.  
slides icon Slides MOPLXGD2 [17.683 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPLXGD2  
About • Received ※ 12 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOIYGD1 Progress in Developing an Accelerator on a Chip laser, acceleration, focusing, photon 16
 
  • R.J. England
    SLAC, Menlo Park, California, USA
  • R.L. Byer
    Stanford University, Stanford, California, USA
  • P. Hommelhoff
    University of Erlangen-Nuremberg, Erlangen, Germany
 
  Acceleration of particles in photonic structures fabricated using semiconductor manufacturing techniques and driven by ultrafast solid state lasers is a new and promising approach to developing future generations of compact particle accelerators. Substantial progress has been made in this area in recent years, fueled by a growing international collaboration of universities, national laboratories, and companies. Performance of these micro-accelerator devices is ultimately limited by laser-induced material breakdown limits, which can be substantially higher for optically driven dielectrics than for radio-frequency metallic cavities traditionally used in modern particle accelerators, allowing for 1 to 2 order of magnitude increase in achievable accelerating fields. The lasers required for this approach are commercially available with moderate (microJoule class) pulse energies and repetition rates in the MHz regime. We summarize progress to date and outline potential near-term applications and offshoot technologies.  
slides icon Slides MOIYGD1 [13.851 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOIYGD1  
About • Received ※ 03 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOOYGD2 The AWAKE Experiment in 2021: Performance and Preliminary Results on Electron-Seeding of Self-Modulation proton, plasma, wakefield, experiment 21
 
  • E. Gschwendtner, L. Verra, G. Zevi Della Porta
    CERN, Meyrin, Switzerland
  • P. Muggli, L. Verra
    MPI, Muenchen, Germany
  • P. Muggli
    MPI-P, München, Germany
  • L. Verra
    TUM, Munich, Germany
 
  The future programme of the Advanced Wakefield (AWAKE) experiment at CERN relies on the seeded self-modulation of an entire proton bunch, resulting in phase-reproducible micro-bunches. This important milestone was achieved during the 2021 proton run by injecting a short electron bunch ahead of the proton bunch, demonstrating for the first time the electron-seeding of proton bunch self-modulation. This talk describes the programme, performance and preliminary results of the AWAKE experiment in the 2021 proton run, and introduces the program of the 2022 proton run. The observation of electron-seeded self-modulation opens new avenues of exploration which will be studied in 2022, including the effect of a phase difference between the front and the back of a proton bunch and the possibility of reproducibly seeding the hosing instability using the electron beam.  
slides icon Slides MOOYGD2 [7.040 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOOYGD2  
About • Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOOYSP1 Impact of Longitudinal Gradient Dipoles on Storage Ring Performance dipole, photon, emittance, storage-ring 30
 
  • F. Zimmermann, Y. Papaphilippou, A. Poyet
    CERN, Meyrin, Switzerland
 
  Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 101004730 (iFAST).
Innovative new magnets with longitudinally varying dipole field are being produced for installation in a few modern light-source storage rings. We investigate some of the associated beam-dynamics issues, in particular the photon spectrum and quantum fluctuation associated with such magnets, and we study whether the resulting equilibrium emittance may deviate from the value expected in the long-magnet limit.
 
slides icon Slides MOOYSP1 [2.364 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOOYSP1  
About • Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOST025 Influences of the Transverse Motions of the Particles to the Recombination Rate of a Co-Propagating Electron-Ion System experiment, alignment, target, cavity 112
 
  • G. Wang, D. Kayran, V. Litvinenko, I. Pinayev, P. Thieberger
    BNL, Upton, New York, USA
  • V. Litvinenko
    Stony Brook University, Stony Brook, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
For a system with the ion beam co-propagating with the electron beam, such as a traditional electron cooler or a Coherent electron Cooler (CeC), the recombination rate is an important observable for matching the energy of the electrons with the ions. In this work, we have developed the analytical expressions to investigate how the recombination rate depends on the energy difference of the two beams, with the influences from the transverse motions of the particles being considered. The analytical results are then used to analyze the measured recombination data collected during the CeC experiment in run 21 and run 22.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST025  
About • Received ※ 09 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOST026 Influences of the Energy Jitter to the Performance of the Coherent Electron Cooling simulation, experiment, kicker, emittance 115
 
  • G. Wang, V. Litvinenko, J. Ma
    BNL, Upton, New York, USA
  • V. Litvinenko
    Stony Brook University, Stony Brook, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
The bandwidth of a coherent electron cooling (CeC) system is typically two to three orders of magnitude higher than the traditional RF based stochastic cooling system, which make it possible to cool the ion bunches with high energy and high intensity. However, for such broad bandwidth, jitters in the energy of the cooling electron bunches present a serious challenge to the performance of the cooling system. In this work, we present analytical as well as simulation studies about the influences of the energy jitter to a CeC system with parameters relevant to the on-going CeC experiment at RHIC.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST026  
About • Received ※ 09 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOST037 Characterisation of Bunch-by-Bunch Tune Shift Effects in the CERN SPS simulation, impedance, injection, kicker 148
 
  • I. Mases Solé, H. Bartosik, V. Kain, K. Paraschou, M. Schenk, C. Zannini
    CERN, Meyrin, Switzerland
 
  After the implementation of major upgrades as part of the LHC Injector Upgrade Project (LIU), the Super Proton Synchrotron (SPS) delivers high intensity bunch trains with 25 ns bunch spacing to the Large Hadron Collider (LHC) at CERN. These beams are exposed to several collective effects in the SPS, such as beam coupling impedance, space charge and electron cloud, leading to relatively large bunch-by-bunch coherent and incoherent tune shifts. Tune correction to the nominal values at injection is crucial to ensure beam stability and good beam transmission. During the beam commissioning of the SPS, measurements of the bunch-by-bunch coherent tune shifts have been conducted under different beam conditions, together with appropriate corrections of the average tunes at each injection. In this paper, we describe the methodology that has been developed to acquire bunch-by-bunch position data and to perform online computations of the coherent tune spectra of each bunch using refined Fourier transform analysis. The experimental data are compared to multiparticle tracking simulations using the SPS impedance model, in view of developing an accurate model for tune correction in the SPS.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST037  
About • Received ※ 03 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOST045 A Novel Tool for Beam Dynamics Studies with Hollow Electron Lenses simulation, collimation, collider, hadron 176
 
  • P.D. Hermes, R. Bruce, R. De Maria, M. Giovannozzi, G. Iadarola, D. Mirarchi, S. Redaelli
    CERN, Meyrin, Switzerland
 
  Hollow Electron Lenses (HELs) are crucial components of the CERN LHC High Luminosity Upgrade (HL-LHC), serving the purpose of actively controlling the population of the transverse beam halo to reduce particle losses on the collimation system. Symplectic particle tracking simulations are required to optimize the efficiency and study potentially undesired beam dynamics effects with the HELs. With the relevant time scales in the collider in the order of several minutes, tracking simulations require considerable computing resources. A new tracking tool, Xsuite, developed at CERN since 2021, offers the possibility of performing such tracking simulations using graphics processing units (GPUs), with promising perspectives for the simulation of hadron beam dynamics with HELs. In this contribution, we present the implementation of HEL physics effects in the new tracking framework. We compare the performance with previous tools and show simulation results obtained using known and newly established simulation setups.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST045  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOST048 Efficient Representation of Realistic 3D Static Magnetic Fields for Symplectic Tracking and First Applications for Frequency Analysis and Dynamic Aperture Studies in ELENA resonance, dynamic-aperture, lattice, emittance 187
 
  • L. Bojtár
    CERN, Meyrin, Switzerland
 
  The algorithm called SIMPA has a new and unique approach to long-term 4D tracking of charged particles in arbitrary static electromagnetic fields. Field values given on the boundary of the region of interest are reproduced by an arrangement of hypothetical magnetic or electric point sources surrounding the boundary surface. The vector and scalar potentials are obtained by summing the contributions of each source. The second step of the method improves the evaluation speed of the potentials and their derivatives by orders of magnitude. This comprises covering the region of interest by overlapping spheres, then calculating the spherical harmonic expansion of the potentials on each sphere. During tracking, field values are evaluated by calculating the solid harmonics and their derivatives inside a sphere containing the particle. Frequency analysis and dynamic aperture studies in ELENA is presented. The effect of the end fields and the perturbation introduced by the magnetic system of the electron cooler on dynamic aperture is shown. The dynamic aperture calculated is the direct consequence of the geometry of the magnetic elements, no multipole errors have been added to the model.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST048  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOST049 Electron Cloud Build-Up for the Arc Sextupole Sections of the FCC-ee collider, simulation, vacuum, sextupole 191
 
  • J.E. Rocha Muñoz, G.H.I. Maury Cuna
    Universidad de Guanajuato, División de Ciencias e Ingenierías, León, Mexico
  • K.B. Cantún-Ávila
    UADY, Mérida, Yucatán, Mexico
  • F. Zimmermann
    CERN, Meyrin, Switzerland
 
  Funding: Consejo Nacional de Ciencia y Tecnología (CONACyT) - México
In particle accelerators that operate with positrons, an electron cloud may occur due to several mechanisms. This work reports preliminary studies on electron cloud build-up for the arc sextupole sections of the positron ring of the FCCe+e using the code PyECLOUD. We compute the electron cloud evolution while varying strategic parameters and consider three simulation scenarios. We report the values of the central density just before the bunch passage, which is related to the single-bunch instability threshold and the electron density threshold for the three scenarios. In addition, we compare the simulated electron distribution across the central circular cross-section for a chamber with and without winglets.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST049  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 25 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOST055 The EIC Rapid Cycling Synchrotron Dynamic Aperture Optimization dynamic-aperture, sextupole, lattice, resonance 210
 
  • H. Lovelace III, C. Montag, V.H. Ranjbar
    BNL, Upton, New York, USA
  • F. Lin
    ORNL RAD, Oak Ridge, Tennessee, USA
 
  With the design of the Electron-Ion Collider (EIC), a new Rapid Cycling Synchrotron (RCS) must be designed to accelerate the electron bunches from 400 MeV up to 18 GeV. An optimized dynamic aperture with preservation of polarization through the energy ramp was found. The codes DEPOL, MAD-X, and BMAD are used in modeling the dynamics and spin preservation. The results will be discussed in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST055  
About • Received ※ 27 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT004 Development of a New Clusterization Method for the GEM-TPC Detector detector, experiment, electronics, ECR 233
 
  • M. Luoma, F. Garcia, A. Jokinen, R. Turpeinen, J. Äystö
    HIP, University of Helsinki, Finland
  • T. Blatz, H. Flemming, K. Götzen, C. Karagiannis, N. Kurz, S. Löchner, C. Nociforo, C.J. Schmidt, H. Simon, B. Voss, P. Wieczorek, M. Winkler
    GSI, Darmstadt, Germany
  • D. Chokheli
    Georgian Technical University, Tbilisi, Georgia
  • T. Grahn, S. Rinta-Antila
    JYFL, Jyväskylä, Finland
 
  The Facility for Antiproton and Ion Research FAIR, in Darmstadt Germany, will be one of the largest accelerator laboratories worldwide. The Superconducting FRagment Separator (Super-FRS)* is one of its main components. The Super-FRS can produce, separate and deliver high-energy radioactive beams with intensities up to 1e11 ions/s, covering projectiles from protons up to uranium and it can be used as an independent experimental device. The Gas Electron Multiplier-based Time Projection Chambers (GEM-TPC) in twin configuration is a newly developed beam tracking detector capable of providing spatial resolution of less than 1 mm with a tracking efficiency close to 100% at 1 MHz counting rate. The GEM-TPC (HGB4) was tested at the FRagment Separator (FRS), with 238U beam at 850 MeV/u. A new clusterization method was developed, for the first time and used for an analysis. This method allowed to access to waveforms of each strip signal within a single trigger in an event-by-event basis. The procedures involved in this method will be shown in details.
* H.Geissel et al., The Super-FRS project at GSI, Nucl. Instr. and Meth. in Phys., vol. B204, pp. 71-85, 2003.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT004  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT005 Bunch Measurements with BPM at Low Energy Hadron Accelerators linac, rfq, simulation, diagnostics 237
 
  • S.M. Ben Abdillah
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • S. Boussa, A. Gatera, F. Pompon
    SCK•CEN, Mol, Belgium
 
  Beam Position Monitors (BPM) are one of the key diagnostics use in LINACs, BPMs should ensure a continuous monitoring of the beam position and energy. BPMs also give an indication of the beam transverse shape. For electron LINACs, beam longitudinal length is measured with BPMs. However, in hadron LINACs, it is performed with intrusive modules (wire scanners, beam shape monitors) This document relates the measurement of beam longitudinal length with BPMs. It is divided in two parts: first, a theoretical model of the BPM operation and the formulas driving the measurement of beam longitudinal length from BPM output signals. Second, an experimental study run at MYRRHA LINAC facility and showing good agreement between estimated values of beam longitudinal length from Tracewin simulations and BPM measurements.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT005  
About • Received ※ 12 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT009 New Bunch-by-Bunch Filling Pattern Measuring System at ELSA FPGA, synchrotron, cavity, controls 244
 
  • A.K. Wald, K. Desch, D. Elsner, D. Proft
    ELSA, Bonn, Germany
 
  The electron accelerator facility ELSA at the University of Bonn, Germany, can accelerate and store electrons with a final energy from 0.8GeV up to 3.2GeV. To routinely determine the filling pattern in the storage ring, a new measuring system has been developed. For hadron physics experiments the filling pattern, which is influenced by the injection from the pre-accelerating synchrotron, should be as homogeneous as possible. The new measurement system should provide a real-time measurement of the filling pattern, so that the injection can be continuously optimized. Moreover, a position measurement for each individual bunch is provided, from which the two transverse and the longitudinal tunes can be deduced. To measure the bunch-by-bunch intensity and position, the signals of the existing button-type BPMs will be digitized by fast 12-bit ADCs synchronized to the 500MHz ELSA radio frequency. The fast pre-processing and intermediate storage of the data is realized with a 500MHz clocked FPGA and transfers the data to a PC for further processing. First results of measurement system developed in-house will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT009  
About • Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT012 Concept of a Beam Diagnostics System for the Multi-Turn ERL Operation at the S-DALINAC cavity, linac, operation, recirculation 254
 
  • M. Dutine, M. Arnold, R. Grewe, L.E. Jürgensen, N. Pietralla, F. Schließmann, M. Steinhorst
    TU Darmstadt, Darmstadt, Germany
 
  Funding: Work supported by DFG (GRK 2128), BMBF (05H21RDRB1), the State of Hesse within the Research Cluster ELEMENTS (Project ID 500/10.006) and the LOEWE Research Group Nuclear Photonics.
The S-DALINAC is a thrice-recirculating electron accelerator operating in cw-mode at a frequency of 3 GHz. Due to the implementation of a path-length adjustment system capable of a 360° phase shift, it is possible to operate the accelerator as an Energy-Recovery LINAC. The multi-turn ERL operation has been demonstrated in 2021. While operating the accelerator in this mode, there are two sets of bunches, the still-to-be accelerated and the already decelerated beam, with largely different absolute longitudinal coordinates in the same beamline acting effectively as a 6 GHz beam. For this mode, a non-destructive, sensitive beam diagnostics system is necessary in order to measure the position of both beams simultaneously. The status of a 6 GHz resonant cavity beam position monitor (BPM) will be given together with the results of a wire scanner measurement of the multi-turn ERL beam.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT012  
About • Received ※ 02 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT013 Comparative Study of Broadband Room Temperature THz Detectors for High and Intermediate Frequency Response detector, experiment, laser, photon 257
 
  • R. Yadav, S. Preu
    IMP, TU Darmstadt, Darmstadt, Germany
  • A. Penirschke
    THM, Friedberg, Germany
 
  Funding: Scholarship from Hesse ministry of science and culture (HMWK), Germany.
Room temperature terahertz (THz) detectors based on Field effect transistors (FETs) and Zero-bias Schottky diodes (SD) are prominent members for the temporal-spatial characterization of pulses down to the picosecond scale generated at particle accelerators. Comparative study of in house developed THz detectors both at higher and intermediate frequency (IF) is carried out using table top THz systems and commercially available sources. In this paper, we present high frequency and intermediate frequency (IF) response of Gallium Arsenide (GaAs) FET and Zero-bias Schottky diode THz detectors. The IF results obtained are helpful for understanding and designing of optimized IF circuit with broader bandwidth.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT013  
About • Received ※ 19 May 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 25 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT016 Update of the Bunch Arrival Time Monitor at ELBE laser, controls, feedback, pick-up 260
 
  • M. Kuntzsch, A. Maalberg, A. Schwarz, K. Zenker
    HZDR, Dresden, Germany
  • M.K. Czwalinna, J. Kral
    DESY, Hamburg, Germany
 
  The bunch arrival time monitor (BAM) at the radiation source ELBE has been upgraded twofold. In order to achieve a higher precision a new frontend has been designed, based on a development by DESY, that uses state of the art 50 GHz electro-optical modulators (EOMs). The frontend allows for thermal control of critical components and monitoring of system parameters. The modulated EOM signals and monitoring data are distributed to a new readout electronic. The new MicroTCA-based receiveris based on a dedicated FMC card developed at DESY that is installed on an FMC25 carrier board. The arrival time is calculated on a FPGA with low latency and can be used for machine diagnostic. The code has been adapted to enable the processing of a data stream of the continuous train of electron bunches, allowing for the implementation of a cw beam based feedback in a next step. The contribution will describe the BAM setup as well as the performance measured at the ELBE accelerator.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT016  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT017 Terahertz Sampling Rates with Photonic Time-Stretch for Electron Beam Diagnostics photon, software, laser, data-acquisition 263
 
  • O. Manzhura, E. Bründermann, M. Caselle, S.A. Chilingaryan, T. Dritschler, S. Funkner, A. Kopmann, A.-S. Müller, M.J. Nasse, G. Niehues, M.M. Patil, J.L. Steinmann
    KIT, Karlsruhe, Germany
  • S. Bielawski, E. Roussel, C. Szwaj
    PhLAM/CERCLA, Villeneuve d’Ascq Cedex, France
  • S. Bielawski, E. Roussel, C. Szwaj
    PhLAM/CERLA, Villeneuve d’Ascq, France
 
  Funding: Supported by the Helmholtz Program-Oriented Funding (PoF), research program Matter and Technologies (Detector Technology and System), ANR-DFG ULTRASYNC funding program, CEMPI LABEX and Wavetech CPER.
To understand the underlying complex beam diagnostic often large numbers of single-shot measurements must be acquired continuously over a long time with extremely high temporal resolution. Photonic time-stretch is a measurement method that is able to overcome speed limitations of con- ventional digitizers and enable continuous ultra-fast single- shot terahertz spectroscopy with refresh rates of trillions of consecutive frames. In this contribution, a novel ultra- fast data sampling system based on photonic time-stretch is presented and the performance is discussed. THERESA (TeraHErtz REadout SAmpling) is a data acquisition system based on the recent ZYNQ-RFSoC family. THERESA has been developed with an analog bandwidth up to 20 GHz and a sampling rate up to 90 GS/s. When combined with the photonic time-stretch setup, the system will be able to sample a THz signal with an unprecedented frame rate of 8 TS/s. Continuous acquisition for long observation times will open up new possibilities in the detection of rare events in accelerator physics.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT017  
About • Received ※ 08 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT018 Advancing to a GHz Transition Radiation Monitor for Longitudinal Charge Distribution Measurements vacuum, radiation, target, simulation 267
 
  • S. Klaproth, A. Penirschke
    THM, Friedberg, Germany
  • H. De Gersem
    TEMF, TU Darmstadt, Darmstadt, Germany
  • T. Reichert, R. Singh
    GSI, Darmstadt, Germany
 
  Funding: This work is supported by the German Federal Ministry of Education and Research (BMBF) under contract no. 05P21RORB2. Joint Project 05P2021 - R&D Accelerator (DIAGNOSE)
In the past, longitudinal beam profiles have been measured with e.g., Feschenko monitors*, Fast Faraday Cups (FFC)** and field monitors. Feschenko monitors usually examine an average shape over several pulses and FFCs are interceptive devices by design. In this work we want to present the progress in the development of a novel GHz diffraction radiation monitor which shall be able to measure the longitudinal charge distribution of single bunches within Hadron beam LINACS non-destructively. A proof-of-concept measurement has been performed at GSI. We aim for a resolution of 50 to 100ps at beam energies of β=0.05 to 0.74. electronic field simulations were performed using CST Particle Studio to determine an optimal RF-Window, which also suits as vacuum chamber and the beam energy and angular dependencies of the diffraction radiation for different materials were analyzed.
* A. V. Feschenko (2001): Methods and Instrumentation for Bunch Shape Measurements. In Proc. PAC’01, paper ROAB002
** G. Zhu et al (2018): Rev. Sci. Instrum. issn 0034-6748, doi :10.1063/1.5027608
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT018  
About • Received ※ 14 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT019 Wakefield Studies for a Bunch Arrival-Time Monitor Concept with Rod-Shaped Pickups on a Printed Circuit Board for X-Ray Free-Electron Lasers pick-up, FEL, wakefield, simulation 271
 
  • B.E.J. Scheible, A. Penirschke
    THM, Friedberg, Germany
  • W. Ackermann, H. De Gersem
    TEMF, TU Darmstadt, Darmstadt, Germany
  • M.K. Czwalinna, H. Schlarb
    DESY, Hamburg, Germany
 
  Funding: This work is supported by the German Federal Ministry of Education and Research (BMBF) under contract No. 05K19RO1.
The European XFEL (EuXFEL) and other notable X-ray Free-Electron Laser facilities rely on an all-optical synchronization system with electro-optical bunch arrival-time monitors (BAM). The current BAMs were benchmarked with a resolution of 3.5 fs for nominal 250 pC bunches at the EuXFEL, including jitter of the optical reference system. The arrival-time jitter could be reduced to about 10 fs with a beam-based feedback system. For future experiments at the EuXFEL the bunch charge will be decreased to a level where the existing system’s accuracy will no longer be sufficient. In simulations a concept based on rod-shaped pickups mounted on a printed circuit board indicated its potential for such low charge applications. For the feasibility of the proposed design, its contribution to the total impedance is essential. In this work the design and an intermediate version are compared to state-of-the-art BAM regarding their wake potential. Furthermore, measures to mitigate wakefields are discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT019  
About • Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 05 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT020 Longitudinal Phase Space Diagnostics with Corrugated Structure at the European XFEL diagnostics, FEL, optics, laser 275
 
  • S. Tomin, W. Decking, N. Golubeva, A.I. Novokshonov, T. Wohlenberg, I. Zagorodnov
    DESY, Hamburg, Germany
 
  Characterization of the longitudinal phase space (LPS) of the electron beam after the FEL process is important for its study and tuning. At the European XFEL, a single plate corrugated structure was installed after the SASE2 undulator to measure the LPS of the electron beam. The beam passing near the plate’s corrugations creates wakefields, which induce a correlation between time and the transverse distribution of the beam. The longitudinal phase space of the beam is then analyzed on a scintillating screen monitor placed in the dispersion section. In this paper, we present the result of commissioning the corrugated structure and the first LPS measurement.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT020  
About • Received ※ 12 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT021 5D Tomography of Electron Bunches at ARES simulation, emittance, quadrupole, synchrotron 279
 
  • S. Jaster-Merz, R.W. Aßmann, R. Brinkmann, F. Burkart, T. Vinatier
    DESY, Hamburg, Germany
  • R.W. Aßmann
    LNF-INFN, Frascati, Italy
  • S. Jaster-Merz
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
 
  The ARES linear accelerator at DESY aims to deliver stable and well-characterized electron bunches with durations down to the sub-fs level. Such bunches are highly sought after to study the injection into novel high-gradient accelerating structures, test diagnostics devices, or perform autonomous accelerator studies. For such applications, it is advantageous to have a complete and detailed knowledge of the beam properties. Tomographic methods have shown to be a key tool to reconstruct the phase space of beams. Based on these techniques, a novel diagnostics method is being developed to resolve the full 5-dimensional phase space (x,x’,y,y’,z) of bunches including their transverse and longitudinal distributions and correlations. In simulation studies, this method shows an excellent agreement between the reconstructed and the original distribution for all five planes. Here, the 5-dimensional phase space tomography method is presented using a showcase simulation study at ARES.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT021  
About • Received ※ 03 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 07 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT025 Development of an Electro-Optical Longitudinal Bunch Profile Monitor at KARA Towards a Beam Diagnostics Tool for FCC-ee laser, operation, collider, polarization 296
 
  • M. Reißig, M. Brosi, E. Bründermann, S. Funkner, B. Härer, A.-S. Müller, G. Niehues, M.M. Patil, R. Ruprecht, C. Widmann
    KIT, Karlsruhe, Germany
 
  Funding: The Future Circular Collider Innovation Study (FCCIS) project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant No 951754. M. R. and M. M. P. acknowledge the support by the Doctoral School "Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology". C. W. achnowledges funding by BMBF contract number 05K19VKD.
The Karlsruhe Research Accelerator (KARA) at KIT features an electro-optical (EO) near-field diagnostics setup to conduct turn-by-turn longitudinal bunch profile measurements in the storage ring using electro-optical spectral decoding (EOSD). Within the Future Circular Collider Innovation Study (FCCIS) an EO monitor using the same technique is being conceived to measure the longitudinal profile and center-of-charge of the bunches in the future electron-positron collider FCC-ee. This contribution provides an overview of the EO near-field diagnostics at KARA and discusses the development and its challenges towards an effective beam diagnostics concept for the FCC-ee.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT025  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT026 Beam Diagnostics for the Storage Ring of the cSTART Project at KIT diagnostics, storage-ring, beam-diagnostic, FEL 300
 
  • D. El Khechen, E. Bründermann, A. Mochihashi, A.-S. Müller, M.-D. Noll, A.I. Papash, R. Ruprecht, P. Schreiber, M. Schuh, J.L. Steinmann
    KIT, Karlsruhe, Germany
 
  In the framework of the compact STorage ring for Accelerator Research and Technology (cSTART) project, which will be realized at Karlsruhe Institute of Technology (KIT), a Very Large Acceptance compact Storage Ring (VLA-cSR) is planned to study the injection and the storage of 50 MeV, ultra-short (sub-ps) electron bunches from a laser plasma accelerator (LPA) and the linac-based test facility FLUTE. For such a storage ring, where a single bunch with a relatively wide range of bunch charge (1 pC - 1000 pC ) and energy spread (10’4 - 10’2) will circulate at a relatively high revolution frequency (7 MHz), the choice of beam diagnostics is very delicate. In this paper, we would like to discuss several beam diagnostics options for the storage ring and to briefly report on several tests that have been or are planned to be realized in our existing facilities.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT026  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT033 Study of Cherenkov Diffraction Radiation for Beam Diagnostics radiation, experiment, diagnostics, beam-diagnostic 320
 
  • H. Hama, K. Nanbu
    Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
 
  Cherenkov diffraction radiation (ChDR) has been paid attention to non-beam-destructive diagnostics in these years. However, the physical understanding of ChDR is not well satisfied yet because of precise experimental observation is not much easier than one expects. Although we do not deny the Cherenkov radiation and ChDR are fully explained by the classical electromagnetics, we encounter a couple of difficulties in actual applications. For instance, the theory is usually established for the far-field observation, in spite of that the radiation is often observed near-field in the realistic beam diagnostic tools employing photon measurements. In addition, the theory, as a matter of course, includes some assumptions which is sometimes not valid for the specific experiments. We have carried out experiments for observation of coherent ChDR in THz frequency region by a using 100 femtosecond electron beam supplied by the t-ACTS accelerator at Tohoku University. In a flame work of this study an FDTD simulation in the large space has been developed as well. In this presentation, we will show the experimental results comparing with both the theory and the simulation.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT033  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT038 Development of Button BPM Electronics for the Bunch by Bunch Feedback System of 4GSR feedback, electronics, storage-ring, booster 332
 
  • S.W. Jang
    KUS, Sejong, Republic of Korea
 
  With the advent of the fourth-generation storage ring, the size of the vertical emittance of the electron beam is expected to be about 100 times smaller than that of the existing generation. In line with the development of accelerator performance, the resolution of the beam position monitor(BPM) should also be further improved, and it can be provide a more stable and uniform beam to end station users through improved bunch by bunch(BbB) feedback system compared to a system called turn by turn or fast feedback. A developed BPM electronics for BbB feedback will be installed in Bessy II booster ring at HZB Research Institute in Germany. BbB feedback BPM electronics with an improved three button BPMs will be used to measure beam position resolution and calculate an information for BbB feedback and then it will apply to the BbB feedback system. In this proceeding, we will describe the development of an upgraded beam position monitor and BPM electronics for BbB feedback.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT038  
About • Received ※ 08 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 02 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT042 Recent AWAKE Diagnostics Development and Operational Results proton, plasma, laser, experiment 343
 
  • E. Senes, S. Burger, M. Krupa, T. Lefèvre, S. Mazzoni, E. Poimenidou, A. Topaloudis, M. Wendt, G. Zevi Della Porta
    CERN, Meyrin, Switzerland
  • P. Burrows, C. Pakuza
    JAI, Oxford, United Kingdom
  • P. Burrows, C. Pakuza
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
  • D.A. Cooke
    UCL, London, United Kingdom
  • J. Wolfenden
    The University of Liverpool, Liverpool, United Kingdom
  • J. Wolfenden
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  The Advanced Wakefield Experiment (AWAKE) at CERN investigates the Plasma-Wakefield acceleration of electrons driven by a relativistic proton bunch. After successfully demonstrating the acceleration process in the AWAKE Run 1, the experiment has now started the Run 2. The AWAKE Run 2 consists of several experimental periods that aim to demonstrate the feasibility of the AWAKE concept beyond the acceleration experiment, showing its feasibility as accelerator for particle physics application. As part of these developments, a dramatic effort in improving the AWAKE instrumentation is sustained. This contribution reports on the current developments of the instrumentation pool upgrade, including the digital camera system for transverse beam profile measurement, beam halo measurement and the spectrometer upgrade studies. The studies on the development of high-frequency beam position monitors are also described.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT042  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT045 Beam Loss Localisation with an Optical Beam Loss Monitor in the CLEAR Facility at CERN beam-losses, photon, detector, experiment 351
 
  • S. Benítez Berrocal, E. Effinger, J.C. Esteban Felipe, W. Farabolini, P. Korysko, A.T. Lernevall, B. Salvachúa
    CERN, Meyrin, Switzerland
  • M. Chen
    University of Huddersfield, Huddersfield, United Kingdom
 
  A prototype of a Beam Loss Monitor based on the detection of Cherenkov light in optical fibres is being developed to measure beam losses in the CERN Super Proton Synchrotron. Several testing campaigns have been planned to benchmark the simulations of the system and test the electronics in the CLEAR facility at CERN. During the first campaigns, the emission of Cherenkov light inside optical fibres and the photodetector characterisation were studied. Fibre-based Beam Loss monitors continuously monitor beam losses over long distances. The localisation of the beam loss could be calculated from the timing of the signals generated by the photosensors coupled at both ends of the optical fibre. The experimental results of an optical fibre Beam Loss Monitor installed in the CLEAR facility are reported in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT045  
About • Received ※ 03 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT046 Linearity and Response Time of the LHC Diamond Beam Loss Monitors in the CLEAR Beam Test Facility at CERN target, detector, beam-losses, operation 355
 
  • S. Morales Vigo, E. Calvo Giraldo, L.A. Dyks, E. Effinger, W. Farabolini, P. Korysko, A.T. Lernevall, B. Salvachúa, C. Zamantzas
    CERN, Meyrin, Switzerland
  • S. Morales Vigo, C.P. Welsch, J. Wolfenden
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  Chemical Vapour Deposition (CVD) diamond detectors have been tested during the Run 2 operation period (2015-2018) as fast beam loss monitors for the Beam Loss Monitoring (BLM) system of the Large Hadron Collider (LHC) at CERN. However, the lack of raw data recorded during this operation period restrains our ability to perform a deep analysis of their signals. For this reason, a test campaign was carried out at the CLEAR beam test facility at CERN with the aim of studying the linearity and response time of the diamond detectors against losses from electron beams of different intensities. The signal build-up from multi-bunched electron beams was also analyzed. The conditions and procedures of the test campaign are explained, as well as the most significant results obtained.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT046  
About • Received ※ 08 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 07 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT048 Design of a Prototype Gas Jet Profile Monitor for Installation Into the Large Hadron Collider at CERN proton, vacuum, experiment, photon 363
 
  • R. Veness, M. Ady, C. Castro Sequeiro, T. Lefèvre, S. Mazzoni, I. Papazoglou, A. Rossi, G. Schneider, O. Sedláček, K. Sidorowski
    CERN, Meyrin, Switzerland
  • P. Forck, S. Udrea
    GSI, Darmstadt, Germany
  • N. Kumar, A. Salehilashkajani, O. Sedláček, C.P. Welsch, H.D. Zhang
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • N. Kumar, A. Salehilashkajani, O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang
    The University of Liverpool, Liverpool, United Kingdom
 
  The Beam-Gas Curtain or BGC is the baseline instrument for monitoring the concentricity of the LHC proton beam with a hollow electron beam for the hollow e-lens (HEL) beam halo suppression device which is part of the High-Luminosity LHC upgrade. The proof-of-principles experiments of this gas-jet monitor have now been developed into a prototype instrument which has been built for integration into the LHC ring and is now under phased installation for operation in the upcoming LHC run. This paper describes the challenges overcome to produce a gas-jet fluorescence monitor for the ultra-high vacuum accelerator environment. It also presents preliminary results from the installation of the instrument at CERN.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT048  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT049 Study on Energy Spectrum Measurement of Electron Beam for Producing MIR-FEL at PBP-CMU Electron Linac Laboratory dipole, FEL, linac, emittance 367
 
  • P. Kitisri, S. Rimjaem, K. Techakaew
    Chiang Mai University, Chiang Mai, Thailand
  • S. Rimjaem
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  At the PBP-CMU Electron Linac Laboratory (PCELL), we aim to produce a mid-infrared free-electron laser (MIR-FEL) for pump-probe experiments in the future. The electron beam is generated from a thermionic cathode radio-frequency (RF) gun with a 1.5-cell cavity before going to an alpha magnet. In this section, some part of the beam is filtered out by using energy slits. The selected part of the beam is then further accelerated by an RF linear accelerator (linac) to get higher energy. This work focuses on the measurement of energy spectrum of electron beam for producing mid-infrared free-electron laser (MIR-FEL). Since our bunch compressor (BC) for the MIR-FEL beamline is an achromat system, the longitudinal distributions of electron beam at the entrance and the exit of the BC are almost the same. Thus, we can measure the longitidinal properties of the beam before it travels to the BC. By using a dipole magnet and a Faraday cup with a slit, we can measure energy spectrum of electron beam before entering the BC. In this study, the ASTRA code is used to investigate the properties of electron beam as well as to design the measuring system. The design results including systematic error of the measuring system are presented and discussed in this contribution. The results from this work can be used as the guideline for the measuring system construction as well as the beam operation.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT049  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 09 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT050 Systematic Study of Electron Beam Measuring Systems at the PBP-CMU Electron Linac Laboratory emittance, quadrupole, linac, simulation 371
 
  • K. Techakaew, S. Rimjaem
    Chiang Mai University, Chiang Mai, Thailand
 
  The linear accelerator system at the PBP-CMU Electron Linac Laboratory (PCELL) is used to produce electron beam with suitable properties for generating coherent teragertz (THz) radiation and mid-infrared free-electron laser (MIR FEL). Optimization of machine parameters to produce short electron bunches with low energy spread and low transverse emittance was focused in this study. We conducted ASTRA simulations including three-dimentional (3D) space charge algorithm and 3D field distributions for radio-frequency (RF) electron gun and all magnets to develop measuring systems. Electron beam energy and energy spread were investigated downstream the RF gun and the RF linac using an alpha magnet and a dipole spectrometer, respectively. The transverse beam emittance was studied using the quadrupole scan technique. By filtering proper portion of electrons before entering the linac, the beam with average energy of 20 MeV and energy spread of 0.1-1% can be achieved for a bunch charge of 100 pC. The systematic error is less than 10% for measuring average energy and energy spread while it is less than 31% for measuring transverse emittance when placing the screen of at least 1.0 m behind the scanning quadrupole magnet. The results of this study were used to develop the measuring setups in our system.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT050  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 13 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT053 A Beam Position Monitor for Electron Bunch Detection in the Presence of a More Intense Proton Bunch for the AWAKE Experiment proton, plasma, radiation, experiment 381
 
  • C. Pakuza, P. Burrows
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
  • P. Burrows, C. Pakuza
    JAI, Oxford, United Kingdom
  • R. Corsini, W. Farabolini, P. Korysko, M. Krupa, T. Lefèvre, S. Mazzoni, E. Senes, M. Wendt
    CERN, Meyrin, Switzerland
 
  The Advanced Proton Driven Plasma Wakefield Experiment (AWAKE) at CERN uses 6 cm long proton bunches extracted from the Super Proton Synchrotron (SPS) at 400 GeV beam energy to drive high gradient plasma wakefields for the acceleration of electron bunches to 2 GeV within a 10 m length. Knowledge and control of the position of both copropagating beams is crucial for the operation of the experiment. Whilst the current electron beam position monitoring system at AWAKE can be used in the absence of the proton beam, the proton bunch signal dominates when both particle bunches are present simultaneously. A new technique based on the generation of Cherenkov diffraction radiation (ChDR) in a dielectric material placed in close proximity to the particle beam has been designed to exploit the large bunch length difference of the particle beams at AWAKE, 200 ps for protons versus a few ps for electrons, such that the electron signal dominates. Hence, this technique would allow for the position measurement of a short electron bunch in the presence of a more intense but longer proton bunch. The design considerations, numerical analysis and plans for tests at the CERN Linear Electron Accelerator for Research (CLEAR) facility are presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT053  
About • Received ※ 20 May 2022 — Revised ※ 09 June 2022 — Accepted ※ 10 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT055 A Gas Jet Beam Profile Monitor for Beam Halo Measurement simulation, experiment, background, diagnostics 389
 
  • O. Stringer, N. Kumar, C.P. Welsch, H.D. Zhang
    The University of Liverpool, Liverpool, United Kingdom
  • N. Kumar, C.P. Welsch, H.D. Zhang
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  Funding: This work was supported by the HL-LHC-UK phase II project funded by STFC under Grant Ref: ST/T001925/1 and the STFC Cockcroft Institute core grant No. ST/G008248/1.
The gas jet beam profile monitor is a non-invasive beam monitor that is currently being commissioned at Cockcroft Institute. It utilises a supersonic gas curtain which transverses the beam at an angle of 45 degrees and measures beam-induced ionisation interactions of the gas to produce a 2D transverse beam profile image. This paper builds upon previously used single-slit skimmers and improves their ability to form the gas jet into a desired distribution for imaging beam halo. A skimmer device removes off-momentum gas particles and forms the jet into a dense thin curtain, suitable for transverse imaging of the beam. The use of a novel double-slit skimmer is shown to provide a mask-like void of gas over the beam core, increasing the relative intensity of the halo interactions for measurement. Such a non-invasive monitor would be beneficial to storage rings by providing real time beam characteristic measurements without affecting the beam. More specifically, beam halo behaviour is a key characteristic associated with beam losses within storage rings.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT055  
About • Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 26 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT056 Commissioning of a Gas Jet Beam Profile Monitor for EBTS and LHC photon, simulation, vacuum, MMI 393
 
  • H.D. Zhang, N. Kumar, A. Salehilashkajani, O. Sedláček, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • M. Ady, T. Lefèvre, S. Mazzoni, I. Papazoglou, A. Rossi, G. Schneider, O. Sedláček, K. Sidorowski, R. Veness
    CERN, Meyrin, Switzerland
  • P. Forck, S. Udrea
    GSI, Darmstadt, Germany
  • N. Kumar, A. Salehilashkajani, O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: This work is supported by the HL-LHC-UK II project funded by STFC and CERN and the STFC Cockcroft core grant No. ST/G008248/1.
A gas jet beam profile monitor was designed for measuring the electron beam at the electron beam test stand (EBTS) for the Hollow electron lens (HEL) and the proton beam in the large hadron collider (LHC). It is partially installed in the LHC during the second long shutdown. The current monitor is tailored to the accelerator environment including vacuum, geometry, and magnetic field for both the EBTS and the LHC. It features a compact design, a higher gas jet density, and a wider curtain size for a better integration time and a larger detecting range. In this contribution, the commissioning of this monitor at the Cockcroft Institute will be discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT056  
About • Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT057 Updates in Efforts to Data Science Enabled MeV Ultrafast Electron Diffraction System network, gun, laser, experiment 397
 
  • S. Biedron, T.B. Bolin, M. Martínez-Ramón, S.I. Sosa Guitron
    UNM-ECE, Albuquerque, USA
  • M. Babzien, M.G. Fedurin, J.J. Li, M.A. Palmer
    BNL, Upton, New York, USA
  • S. Biedron
    UNM-ME, Albuquerque, New Mexico, USA
  • D. Martin, M.E. Papka
    ANL, Lemont, Illinois, USA
 
  Funding: Work supported by DOEs EPSCoR award DE-SC0021365, used resources of the Brookhaven National Laboratory’s Accelerator Test Facility and of the Argonne Leadership Computing Facility.
MeV ultrafast electron diffraction (MUED) is a pump-probe characterization technique to study ultrafast phenomena in materials with high temporal and spatial resolution. This complex instrument can be advanced into a turn-key, high-throughput tool with the aid of machine learning (ML) mechanisms and high-performance computing. The MUED instrument at the Accelerator Test Facility in Brookhaven National Laboratory was employed to test different ML approaches for both data analysis and control. We characterized different materials using MUED, mainly polycrystalline gold and single crystal Ta2NiS5. Diffraction patterns were acquired in single shot mode and convolutional neural network autoenconder models were evaluated for noise reduction and the reconstruction error was studied to identify anomalous diffraction patterns. Electron beam energy jitter was analyzed from single shot diffraction patterns to be used as a novel diagnostic tool. The MUED beamline was also simulated using VSim to construct a surrogate model for control of beam shape and energy. Progress towards ML-based controls leveraging off Argonne Leadership Computing Facility resources will also be presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT057  
About • Received ※ 02 July 2022 — Accepted ※ 26 June 2022 — Issue date ※ 08 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT058 Machine Learning Training for HOM Reduction in a TESLA-Type Cryomodule at FAST HOM, cavity, emittance, experiment 400
 
  • J.A. Diaz Cruz
    UNM-ECE, Albuquerque, USA
  • J.A. Diaz Cruz, A.L. Edelen, B.T. Jacobson, J.P. Sikora
    SLAC, Menlo Park, California, USA
  • D.R. Edstrom, A.H. Lumpkin, R.M. Thurman-Keup
    Fermilab, Batavia, Illinois, USA
 
  Low emittance electron beams are of high importance at facilities like the Linac Coherent Light Source II (LCLS-II) at SLAC. Emittance dilution effects due to off-axis beam transport for a TESLA-type cryomodule (CM) have been shown at the Fermilab Accelerator Science and Technology (FAST) facility. The results showed the correlation between the electron beam-induced cavity high-order modes (HOMs) and the Beam Position Monitor (BPM) measurements downstream the CM. Mitigation of emittance dilution can be achieved by reducing the HOM signals. Here, we present a couple of Neural Networks (NN) for bunch-by-bunch mean prediction and standard deviation prediction for BPMs located downstream the CM.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT058  
About • Received ※ 15 June 2022 — Revised ※ 18 June 2022 — Accepted ※ 24 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT062 Foil Focusing Effect in Pepper-Pot Measurements in Intense Electron Beams emittance, focusing, solenoid, experiment 404
 
  • S. Szustkowski, M.A. Jaworski, D.C. Moir
    LANL, Los Alamos, New Mexico, USA
 
  Funding: Work supported by the US Department of Energy through the Los Alamos National Laboratory. Los Alamos National Laboratory is operated by Triad National Security, LLC, for the National Nuclear Security Administration of the U.S. Department of Energy (Contract No. 89233218CNA000001).
Thin conducting foils, such as pepper-pot masks, perpendicular to an oncoming intense electron beam acts like an imperfect axisymmetric lens. The beamlets distribution from a pepper-pot mask varies based on if the mask hole radius is smaller or larger than the beams Debye length. Correcting for focusing effect is necessary for measuring transverse emittance with pepper-pot technique for intense electron beams. The Dual Axis Radiographic Hydrodynamic Test Facility (DARHT) Axis-I produces a 20 MeV, 2 kA, 80 ns FWHM electron beam for flash radiography. In this paper, we explore the effect of foil focusing due to various pepper-pot masks at DARHT Axis-I injector region from a 55 mm velvet cathode.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT062  
About • Received ※ 01 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT066 Gas Sheet Diagnostics Using Particle in Cell Code simulation, diagnostics, plasma, experiment 410
 
  • M. Yadav, P. Manwani, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • G. Andonian
    RadiaBeam, Santa Monica, California, USA
  • Ö. Apsimon, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • N.M. Cook, A. Diaw, C.C. Hall
    RadiaSoft LLC, Boulder, Colorado, USA
  • N.P. Norvell
    UCSC, Santa Cruz, California, USA
 
  Funding: This work was supported by the STFC Liverpool Centre for Doctoral Training on Data Intensive Science (LIV. DAT) under grant agreement ST/P006752/1 and DE-SC0019717.
When intense particle beam propagates in dense plasma or gas, ionization can yield valuable information on the drive beam properties. Impact ionization and tunnel ionization are the two ionization regimes that must be accounted for varying beam properties. Due to these ionization mechanisms, new plasma electrons are generated causing different instabilities, dependent on the dominant ionization process considered. In order to accomplish the ambitious experimental goals of sophisticated beam diagnostics using ionization imaging, careful studies on the different ionization regimes, and the cross-over periods, required. Here we will discuss the impact ionization using fully parallel PIC code OSIRIS. We focus on understanding the gas sheet ionization diagnostics for characterizing high intensity charged particle beams. We study the interaction of neutral gas with an electron beam and varying density. We will also investigate the principle of detecting photon emission, rather than direct primary ion imaging, from the ionization induced in the interaction between the gas jet and charged particle beams.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT066  
About • Received ※ 07 June 2022 — Revised ※ 19 June 2022 — Accepted ※ 21 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOPT067 Electron Beam Phase Space Reconstruction From a Gas Sheet Diagnostic simulation, diagnostics, network, experiment 414
 
  • N.M. Cook, A. Diaw, C.C. Hall
    RadiaSoft LLC, Boulder, Colorado, USA
  • G. Andonian
    RadiaBeam, Santa Monica, California, USA
  • N.P. Norvell
    UCSC, Santa Cruz, California, USA
  • M. Yadav
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics under Award Number DE-SC0019717.
Next generation particle accelerators craft increasingly high brightness beams to achieve physics goals for applications ranging from colliders to free electron lasers to studies of nonperturbative QED. Such rigorous requirements on total charge and shape introduce diagnostic challenges for effectively measuring bunch parameters prior to or at interaction points. We report on the simulation and training of a non-destructive beam diagnostic capable of characterizing high intensity charged particle beams. The diagnostic consists of a tailored neutral gas curtain, electrostatic microscope, and high sensitivity camera. An incident electron beam ionizes the gas curtain, while the electrostatic microscope transports generated ions to an imaging screen. Simulations of the ionization and transport process are performed using the Warp code. Then, a neural network is trained to provide accurate estimates of the initial electron beam parameters. We present initial results for a range of beam and gas curtain parameters and comment on extensibility to other beam intensity regimes.

 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT067  
About • Received ※ 08 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 10 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK003 Absorbed Dose Characteristics for Irradiation Experiments at AREAL 5 MeV Electron Linac experiment, radiation, simulation, gun 429
 
  • V.G. Khachatryan, Z. Amirkhanyan, H. Davtyan, A. Grigoryan, B. Grigoryan, M. Ivanyan, V.H. Petrosyan, A. Vardanyan, A.S. Yeremyan
    CANDLE SRI, Yerevan, Armenia
  • A. Grigoryan
    YSU, Yerevan, Armenia
 
  Existing electron photogun facility at the CANDLE SRI currently can provide electron beam with the energy up to 5 MeV. The beam is being used as an irradiation source in the number of material science and life science experiments. Performed beam particle tracking simulations along with intensive application of the beam diagnostic instruments (bending magnet, YAG stations, Faraday cups) allow control of the experimental samples’ irradiation parameters, particularly exposure times for given dose as well as absorbed dose spatial distribution. Direct application of the electron beam for the irradiation experiments allows achievement of high absorbed dose. For the calculation of the irradiation parameters of the experimental samples’ particle transport simulation results should be combined with the beam current measurements by Faraday Cup (FC). Dose measurements and the comparison with numerical simulations using various initial parameters (Transverse size, divergence and energy spread) permit to pin down their actual values.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK003  
About • Received ※ 03 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 02 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK012 Concept of a Polarized Positron Source for CEBAF positron, target, cavity, experiment 457
 
  • S.H. Habet, R.M. Bodenstein, S.A. Bogacz, J.M. Grames, A.S. Hofler, R. Kazimi, F. Lin, M. Poelker, Y. Roblin, A. Seryi, R. Suleiman, A.V. Sy, D.L. Turner
    JLab, Newport News, Virginia, USA
  • A. Ushakov
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • C.A. Valerio-Lizárraga
    ECFM-UAS, Culiacan, Sinaloa, Mexico
  • E.J-M. Voutier
    LPSC, Grenoble Cedex, France
 
  Funding: Laboratoire de Physique des 2 Infinis Irène Joliot-Curie Université Paris-Saclay -> Eric Voutier : eric.voutier@ijclab.in2p3.fr.
Positron beams would provide new and meaningful probes for the experimental program at the Thomas Jefferson National Accelerator Facility (JLab), including but not limited to future hadronic physics and dark matter experiments. Critical requirements involve generating positron beams with a high degree of spin polarization, sufficient intensity and a continuous-wave (CW) bunch train compatible with acceleration to 12 GeV at the Continuous Electron Beam Accelerator Facility (CEBAF). To address these requirements, a polarized positron injector based upon the bremsstrahlung of an intense CW spin polarized electron beam is considered*. First a polarized electron beam line provides >1 mA of polarized electrons at ~120 MeV to a high-power target for positron production. Next, a second beam line collects, shapes and aligns the spin of positrons for users. Finally, the positron beam is matched into the CEBAF acceptance for acceleration and transport to the end stations with energies up to 12 GeV. An optimized layout to provide positrons beams with intensity >100 nA (polarized) or intensity >3 µA (unpolarized) will be discussed in this poster.
* D. Abbott et al., "Production of Highly Polarized Positrons Using Polarized Electrons at MeV Energies", Phys. Rev. Lett., 116, 214801 (2016)
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK012  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK013 Machine Learning Based Surrogate Model Construction for Optics Matching at the European XFEL optics, simulation, quadrupole, FEL 461
 
  • Z.H. Zhu, Y. Chen, W. Qin, M. Scholz, S. Tomin
    DESY, Hamburg, Germany
 
  Beam optics matching is a daily routine in the operation of an X-ray free-electron laser facility. Usually, linear optics is employed to conduct the beam matching in the control room. However, the collective effects like space charge dominate the electron bunch in the low-energy region which decreases the accuracy of the existing tool. Therefore, we proposed a scheme to construct a surrogate model with nonlinear optics and collective effects to speed up the optics matching in the European XFEL injector section. This model also facilitates further research on beam dynamics for the space-charge dominated beam.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK013  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK016 Arc Compressor Test in a Synchrotron - the ACTIS Project linac, synchrotron, radiation, detector 473
 
  • M. Rossetti Conti, A. Bacci, I. Drebot, V. Petrillo, A.R. Rossi, M. Ruijter, L. Serafini
    INFN-Milano, Milano, Italy
  • A. Curcio
    CLPU, Villamayor, Spain
  • S. Di Mitri
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • G.W. Kowalski, R. Panaś, A.I. Wawrzyniak
    NSRC SOLARIS, Kraków, Poland
  • V. Petrillo
    Universita’ degli Studi di Milano, Milano, Italy
  • E. Puppin
    Politecnico/Milano, Milano, Italy
 
  ACTIS (Arc Compressor Test In a Synchrotron) is an experiment aimed to demonstrate the reliability of arc compressors as lattices capable to increase peak current and brightness of an electron beam as it is bent at large angles. This kind of devices has been proposed at theoretical level in several works over the past decades and could be the key to achieve compact and sustainable Free Electron Lasers in the near future. The experiment has been developed since 2019 in the joint effort between INFN, Solaris National Synchrotron Radiation Center and Elettra - S.T. S.C.p.A. The experiment will take place at Solaris (Kraków). Solaris is a synchrotron whose ring is injected by a 550 MeV linac that will be used to prepare the beam with a proper chirp. ACTIS involves also the commissioning of two beam length detectors to be installed downstream of the linac and of the first ring lap. In addition, the low energy model of the machine was built to identify the optimal working point for the experiment and to foresee the longitudinal profile of the beam that will be measured. In this work we present the experiment and report first results obtained in the study phase.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK016  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK022 A Design Study of Injector System for Synchrotron Light Source linac, gun, cavity, simulation 485
 
  • C. Kim, E.-S. Kim, C.S. Park
    KUS, Sejong, Republic of Korea
 
  This work presents a design study of a 200 MeV electron linear accelerator consisting of an electron gun, bunchers, and accelerator structures. We aimed to design the linac with low emittance and low energy spread. A coasting beam from a thermionic electron gun is bunched using a series of buncher cavities: sub-harmonic buncher (SHB), a pre-buncher (PB), and a Buncher. The bunched beam is then accelerated up to 200 MeV with 4 cascaded accelerating structures. The SHB was designed with one-cell standing wave structure for improving the bunching efficiency. The two types of the 500 MHz SHB were considered: elliptical and coupled-cavity linac types. We also investigated constant-gradient and constant-impedance types of 3 GHz multi-cell traveling wave resonators for following buncher cavities and accelerating structures. Depending on the type, geometries of each traveling wave structure (TWS) cavity were determined, and then the electromagnetic fields were calculated. RF powers and phases of each cavity along this linac system were optimized using beam dynamics simulation. Furthermore, the beam distributions in the transverse direction are adjusted using solenoid magnets in the lowenergy section as well as quad triplets in the high-energy section.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK022  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 10 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK023 Beam Dynamics Studies on the 50 MeV Electron Linear Accelerator for Ultra-High Dose Rates gun, acceleration, cavity, cathode 489
 
  • Y. Lee, C. Kim, E.-S. Kim, C.S. Park
    KUS, Sejong, Republic of Korea
  • H.-S. Lee, H.S. Shin
    VITZRONEXTECH, Ansan-si, Gyeonggi-do, Republic of Korea
 
  Electron beams with ultra-high dose rates (>40 Gy/s), which enable effective radiotherapy to act on deep-seated tumors in less than a second, can be generated by linear accelerators. To successfully achieve FLASH radiotherapy, we have performed the 50 MeV linear accelerator design studies. The designed electron accelerator consists of a thermionic electron gun, sub-harmonic buncher, buncher and 2.856 GHz traveling wave structure. In this report the design layout and particle tracking simulation results of the 50 MeV electron linac with high beam current are presented in detail.
FLASH radiotherapy
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK023  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 15 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK026 Four-Dimensional Emittance Measurements and Correction of UED Optics up to Sextupole Order emittance, quadrupole, sextupole, solenoid 496
 
  • W.H. Li, M.B. Andorf, A.C. Bartnik, I.V. Bazarov, C.J.R. Duncan, M. Kaemingk, S.J. Levenson, J.M. Maxson, C.A. Pennington
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • M.A. Gordon, Y.K. Kim
    University of Chicago, Chicago, Illinois, USA
 
  Funding: U.S Department of Energy, grant DE-SC0020144 U.S. National Science Foundation Grant PHY-1549132, the Center for Bright Beams
Ultrafast electron diffraction imposes stringent constraints on the full 6D brightness of the probe electron beam. The desired normalized emittance, often in the few-nanometer regime and below, renders the beam very sensitive to field aberrations and space charge effects. In this proceeding, we report the correction of normal quadrupole, skew quadrupole, and sextupole aberrations in the MEDUSA ultrafast electron micro-diffraction beamline and measurements of the subsequent emittance. This low emittance is enabled by alkali-antimonide photocathodes driven at the photoemission threshold. We demonstrate that the measured emittance is consistent with that of optimized simulations with these cathodes, indicating that low emittance beams from high quality photocathodes can be preserved and used in practical applications.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK026  
About • Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 20 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK027 Characterization of Various GaN Samples for Photoinjectors cathode, polarization, ECR, brightness 500
 
  • M.B. Andorf, I.V. Bazarov, S.J. Levenson, J.M. Maxson
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • J. Encomendero, D. Jena, V.V. Protasenko, H.G. Xing
    Cornell University, Ithaca, New York, USA
 
  Funding: DOE-HEP DESC0021002 DOE-NP DE-SC0021425
Photoemission properties (quantum efficiency, spectral response, and lifetime) of various GaN based photocathodes are summarized, including p-doped samples in its hexagonal phase, cubic GaN and a more exotic 2-D hole gas sample. The 2-D hole contains no dopant impurity but achieves high conductivity via polarization fields produced at the heterojunction of GaN and AlN. For efficient electron production, cesium is used to achieve Negative Electron Affinity.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK027  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK041 Magnetic Field Noise Search Using Turn-by-Turn Data at CESR kicker, power-supply, simulation, synchrotron 553
 
  • V. Khachatryan, J. Barley, M.H. Berry, A.T. Chapelain, D.L. Rubin, J.P. Shanks, S. Wang
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  Funding: The authors thank NSF PHYS-1416318 and DMR-1829070.
A method for searching for magnetic field noise has been developed using the CESR beam turn-by-turn data. The technique is tested using Monte-Carlo samples and turn-by-turn real data with induced noise in one of the CESR magnets. We estimate the analysis sensitivity for the noise sources slower than 4 kHz (or 100 CESR-turns) with the current CESR BPM system on the level of 1 microradian or 0.2 Gs×m field integral. In this work we report the observed noise sources and the improvements achieved by applying this technique. Long-term, several hours, beam stability analysis is also performed using the same method.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK041  
About • Received ※ 07 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 27 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK046 Design Concept for a Second Interaction Region for the Electron-Ion Collider hadron, optics, collider, detector 564
 
  • B.R. Gamage, V. Burkert, R. Ent, Y. Furletova, D.W. Higinbotham, T.J. Michalski, R. Rajput-Ghoshal, D. Romanov, T. Satogata, A. Seryi, C. Weiss, W. Wittmer, Y. Zhang
    JLab, Newport News, Virginia, USA
  • E.C. Aschenauer, J.S. Berg, K.A. Drees, A. Jentsch, A. Kiselev, C. Montag, R.B. Palmer, B. Parker, V. Ptitsyn, F.J. Willeke, H. Witte
    BNL, Upton, New York, USA
  • C. Hyde
    ODU, Norfolk, Virginia, USA
  • F. Lin, V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
  • P. Nadel-Turonski
    SBU, Stony Brook, New York, USA
 
  Funding: Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177, Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 and UT-Battelle, LLC, under contract No. DE-AC05-00OR22725
In addition to the day-one primary Interaction Region (IR), the design of the Electron Ion Collider (EIC) must support operation of a 2nd IR potentially added later. The 2nd IR is envisioned in an existing experimental hall at RHIC IP8, compatible with the same beam energy combinations as the 1st IR over the full center of mass energy range of ~20 GeV to ~140 GeV. The 2nd IR is designed to be complementary to the 1st IR. In particular, a secondary focus is added in the forward ion direction of the 2nd IR hadron beamline to optimize its capability in detecting particles with magnetic rigidities close to those of the ion beam. We provide the current design status of the 2nd IR in terms of parameters, magnet layout and beam dynamics.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK046  
About • Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK047 Cooling Performance in a Dual Energy Storage Ring Cooler proton, storage-ring, damping, cavity 568
 
  • B. Dhital, G.A. Krafft
    ODU, Norfolk, Virginia, USA
  • Y.S. Derbenev, D. Douglas, G.A. Krafft, H. Zhang, Y. Zhang
    JLab, Newport News, Virginia, USA
  • F. Lin, V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
 
  Funding: EIC fellowship at Jefferson Lab
The longitudinal and transverse emittance growth in hadron beams due to intra-beam scattering (IBS) and other heating sources deteriorate the luminosity in a collider. Hence, a strong hadron beam cooling is required to reduce and preserve the emittance. The cooling of high energy hadron beam is challenging. We propose a dual energy storage ring-based electron cooler that uses an electron beam to extract heat away from hadron beam in the cooler ring while the electron beam is cooled by synchrotron radiation damping in the high energy damping ring. In this paper, we present a design of a dual energy storage ring-based electron cooler. Finally, the cooling performance is simulated using Jefferson Lab Simulation Package for Electron Cooling (JSPEC) for proton beams at the top energy of 275 GeV for Electron-Ion Collider.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK047  
About • Received ※ 06 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK051 Modeling a Nb3Sn Cryounit in GPT at UITF cavity, SRF, simulation, gun 576
 
  • S. Pokharel, G.A. Krafft
    ODU, Norfolk, Virginia, USA
  • A.S. Hofler, G.A. Krafft
    JLab, Newport News, Virginia, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
Nb3Sn is a prospective material for future superconducting RF (SRF) accelerator cavities. The material can achieve higher quality factors, higher temperature operation and potentially higher accelerating gradients (Eacc 96 MV/m) compared to conventional niobium. In this work, we performed modeling of the Upgraded Injector Test Facility (UITF) at Jefferson Lab utilizing newly constructed Nb3Sn cavities. We studied the effects of the buncher cavity and varied the gun voltages from 200-500 keV. We have calibrated and optimized the SRF cavity gradients and phases for the Nb3Sn five-cell cavities energy gains with the framework of General Particle Tracer (GPT). Our calculations show the beam goes cleanly through the unit. There is full energy gain out of the second SRF cavity but not from the first SRF cavity due to non-relativistic phase shifts.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK051  
About • Received ※ 20 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK060 An Induction-Type Septum Magnet for the EIC Complex septum, injection, induction, extraction 603
 
  • N. Tsoupas, D. Holmes, C. Liu, I. Marneris, C. Montag, V. Ptitsyn, V.H. Ranjbar, J.E. Tuozzolo
    BNL, Upton, New York, USA
  • B. Bhandari
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
The electron Ion Collider (eIC) project* has been approved by the Department of Energy to be built at the site of Brookhaven National Laboratory (BNL). Part of the eIC accelerator complex and more specifically the Rapid Cycling Syncrotron (RCS) which accelerates the electron beam up to 18 GeV and the electron Storage Ring (eSR) which stores the electron beam bunces for collisions with the hadrons, will be built inside the tunnel of the Relativistic Heavy Ion Collider (RHIC)**. This paper provides information on the electromagnetic design of the septa magnets which will be employed to inject and extract the beam to and from the two synchrotrons used for the acceleration and storage of the electron beam bunches. The type of the septum is of induction type made o laminated iron and it is similar to the one described in ref.[3] The electromagnetic study is performed by the use of the transient module of the OPERA computer code***.
* https://ww.bnl.gov/eic/
** A. Zhuravlev, et al. PIPAC2013, Shanghai, China
*** https://www.3ds.com/products-services/simulia/products/opera/
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK060  
About • Received ※ 05 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOTK066 Damping-Ring-Free Injector Design for Linear Colliders emittance, cavity, SRF, laser 614
 
  • T. Xu, P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
  • S.Y. Kim, P. Piot, J.G. Power
    ANL, Lemont, Illinois, USA
  • M. Kuriki
    HU/AdSM, Higashi-Hiroshima, Japan
 
  Funding: This work was supported by the US DOE contracts # DE-SC0018656 and # DE-SC0018234 (U.S.-Japan Science & Technology Cooperation Program in HEP) with NIU and No.DE-AC02-06CH11357 with ANL.
The current designs of future electron-positron linear colliders incorporate large and complex damping rings to produce asymmetric beams for beamstrahlung mitigation at the interaction point. This paper presents the design of an damping-ring-free electron injector capable of delivering flat electron beams with phase-space partition comparable to the electron-beam parameters produced downstream of the damping ring in the proposed international linear collider (ILC) design. The performance of the proposed configuration, its sensitivity to jitter along with its impact on spin-polarization is discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK066  
About • Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 13 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS001 Progress on Development of AXSIS: A Femtosecond THz-Driven MeV Accelerator and keV X-Ray Source acceleration, gun, linac, laser 621
 
  • N.H. Matlis, M. Fakhari, F.X. Kärtner, T. Kroh, M. Pergament, T. Rohwer, M. Vahdani, D. Zhang
    CFEL, Hamburg, Germany
  • R. Bazrafshan, F.X. Kärtner, T. Rohwer
    Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
  • R. Bazrafshan, M. Vahdani
    University of Hamburg, Hamburg, Germany
  • M. Fakhari, D. Zhang
    DESY, Hamburg, Germany
  • F.X. Kärtner, T. Kroh
    The Hamburg Center for Ultrafast Imaging, University of Hamburg, Hamburg, Germany
 
  Funding: This work was supported by KA908-12/1 of the Deutsche Forschungsgemeinschaft and by the ERC under the European Union’s Seventh Framework Program (FP7/2007-2013) through Synergy Grant AXSIS (609920).
We report on the design and progress in implementing a THz-driven relativistic electron accelerator and associated X-ray source, the AXSIS Facility at DESY. We have developed a full layout of the machine based on a THz gun followed by a multi-cycle dielectric loaded metal waveguide THz linear accelerator to generate 20 MeV level, 10 fs electron bunches. The required THz pulse energies are on the mJ-level for the gun and multi-10-mJ-level for the THz linac. Customized laser technologies have been developed allowing for the generation of these pulses up to 1 kHz repetition rate. The generated electron bunches are then focused into a counter propagating optical pulse ’optical undulator’ to generate X-rays in the 6-7 keV range. We will discuss the overall layout of the machine, status of its implementation and technical challenges in the different components as well as diagnostics of this new type of accelerator and X-ray source.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS001  
About • Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS003 Single-Sided Pumped Compact Terahertz Driven Booster Accelerator booster, gun, acceleration, experiment 625
 
  • T. Kroh, R. Bazrafshan, F.X. Kärtner, N.H. Matlis
    Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
  • M. Fakhari, M. Pergament, T. Rohwer, M. Vahdani, D. Zhang
    CFEL, Hamburg, Germany
  • F.X. Kärtner
    The Hamburg Center for Ultrafast Imaging, University of Hamburg, Hamburg, Germany
  • K. Kawase
    JAEA, Kizugawa, Japan
 
  Funding: European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) through the Synergy Grant ’Frontiers in Attosecond X-ray Science: Imaging and Spectroscopy’ (609920).
Scaling the RF-accelerator concept to terahertz (THz) frequencies brings several compelling advantages, including compactness, intrinsic timing between the photoemission and driving field sources, and high field gradients associated with the short THz wavelength and high breakdown threshold. Recent demonstrations of such THz powered accelerators relied on two counter-propagating single-cycle THz pulses. However, to achieve high energy gains in the acceleration process high energy THz pulses are needed which in turn require complex optical setups. Here, we present on the development of a matchbox sized multi-layered accelerator designed to boost the 50 keV output of a DC electron gun to energies of ~400 keV that only requires a single THz pulse to be powered. An integrated tunable mirror inside the structure interferes the front of the driving THz pulse with its rear part such that the field in the interaction region is optimized for efficient acceleration. This reduces the complexity of the required optical setup. Such a compact booster accelerator is very promising as electron source in ultrafast electron diffraction experiments and as booster stage prior to THz based LINACs.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS003  
About • Received ※ 08 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 20 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS004 Optimizing Activation Recipe with Cs, Te, O for GaAs-Based Photocathodes cathode, site, vacuum, polarization 628
 
  • J. Bae, M.B. Andorf, I.V. Bazarov, A. Galdi, J.M. Maxson
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • L. Cultrera
    BNL, Upton, New York, USA
 
  Funding: Department of Energy (DOE) DE-SC0021039.
GaAs-based photocathodes are the most popular electron sources for producing highly spin-polarized electron beams in accelerator physics and condensed matter physics. Spin-polarized photoemission requires activation to achieve Negative Electron Affinity (NEA). Conventional NEA surfaces such as CS-O/NF3 are extremely vacuum sensitive, and this results in rapid QE degradation. In this work, we activated GaAs with various recipes using Cs, Te, and oxygen. We demonstrate NEA activation on GaAs surfaces. Among Cs-Te activated samples, the oxidized sample showed the highest QE and longest lifetime at 780 nm.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS004  
About • Received ※ 04 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS005 Start-to-End Simulations of a THz-Driven ICS Source linac, gun, simulation, photon 631
 
  • M. Fakhari, Y.-K. Kan
    DESY, Hamburg, Germany
  • F.X. Kärtner
    The Hamburg Center for Ultrafast Imaging, University of Hamburg, Hamburg, Germany
  • F.X. Kärtner
    Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
  • N.H. Matlis, M. Vahdani
    CFEL, Hamburg, Germany
  • M. Vahdani
    University of Hamburg, Hamburg, Germany
 
  We present start-to-end simulations for a fully THz-driven table-top X-ray source. A dielectric-loaded metallic cavity operating at its Higher Order Mode accelerates 1 PC photo emitted electron bunch up to 430 keV kinetic energy. The output beam of the gun is injected into a dielectric-loaded waveguide where phase velocity of the traveling wave is adjusted in such a way that electrons see an accelerating field all the way along the tube resulting to an 18.5-MeV output beam which is then transported to an inverse Compton scattering (ICS) stage. The injection phase of the electrons can be tuned to introduce a negative energy chirp to the electron bunch leading to a ballistic bunch compression after the linac. In addition, a set of permanent magnet quadrupoles is designed to focus the beam at the ICS interaction point where the electron beam scatters off a 250-mJ, 0.5ps, 1-µm laser beam and generates an X-ray beam with 2.6x107 photons per shot containing photon energies 2keV< Eph <8keV in a beam with 50 mrad half opening angle. The required terahertz waves to power the gun and linac are 550-ps pulses at 300 GHz containing 5 mJ and 23 mJ energies respectively with 1 kHz repetition rate.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS005  
About • Received ※ 08 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 25 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS007 Optimized Dielectric Loaded Waveguide Terahertz LINACs acceleration, linac, GUI, vacuum 634
 
  • M. Vahdani
    University of Hamburg, Hamburg, Germany
  • M. Fakhari
    DESY, Hamburg, Germany
  • F.X. Kärtner
    The Hamburg Center for Ultrafast Imaging, University of Hamburg, Hamburg, Germany
  • F.X. Kärtner
    Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
  • M. Vahdani
    CFEL, Hamburg, Germany
 
  Dielectric loaded waveguides (DLW) powered by multicycle terahertz (THz) pulses have shown promising performance as compact linear accelerators due to higher breakdown fields at THz frequencies compared to conventional RF components. By changing the dielectric dimensions one can control phase and group velocities of the THz pulse inside the DLW. Since optimum waveguide dimensions are dependent on initial electron energy, THz pulse energy, and etc., it is worthwhile to determine optimum values for different conditions to maximize final kinetic energy. In this work, we present a combined analytical/numerical guide to determine the optimum DLW parameters for single on-axis electron acceleration. We also introduce normalized graphic representations to visualize optimum designs for different initial electron and THz pulse energies.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS007  
About • Received ※ 09 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS014 Commissioning of a High-Gradient X-Band RF Gun Powered by Short RF Pulses from a Wakefield Accelerator gun, laser, cathode, MMI 652
 
  • W.H. Tan, X. Lu, P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
  • S.P. Antipov, C.-J. Jing, E.W. Knight, S.V. Kuzikov
    Euclid TechLabs, Solon, Ohio, USA
  • D.S. Doran, G. Ha, C.-J. Jing, W. Liu, X. Lu, P. Piot, P. Piot, J.G. Power, J. Shao, C. Whiteford, E.E. Wisniewski
    ANL, Lemont, Illinois, USA
 
  Funding: This work is supported by the U.S. DOE, under award No. DE-SC0018656 to NIU, DOE SBIR grant No DE-SC0018709 at Euclid Techlabs LLC, and contract No. DE-AC02-06CH11357 with ANL.
A high-gradient X-band (11.7-GHz) photoinjector developed by Euclid Techlabs, was recently commissioned at the Argonne Wakefield Accelerator (AWA). The system comprises a 1+1/2-cell RF gun powered by short RF pulses generated as a train of high-charge bunches from the AWA accelerator passes through a slow-wave power extraction and transfer structure. The RF photoinjector was reliably operating with electric fields in excess of 300 MV/m on the photocathode surface free of breakdown and with an insignificant dark-current level. We report on the RF-gun setup, commissioning, and the associated beam generation via photoemission.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS014  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS015 Temporal and Spatial Characterization of Ultrafast Terahertz Near-Fields for Particle Acceleration acceleration, simulation, radiation, laser 656
 
  • A.E. Gabriel, M.C. Hoffmann, E.A. Nanni, M.A.K. Othman
    SLAC, Menlo Park, California, USA
 
  Funding: This work was supported by Department of Energy contract DE-AC02-76SF00515.
We have measured the THz near-field in order to inform the design of improved THz-frequency accelerating structures. THz-frequency accelerating structures could provide the accelerating gradients needed for next generation particle accelerators with compact, GV/m-scale devices. One of the most promising THz generation techniques for accelerator applications is optical rectification in lithium niobate using the tilted pulse front method. However, accelerator applications are limited by significant losses during transport of THz radiation from the generating nonlinear crystal to the acceleration structure. In addition, the spectral properties of high-field THz sources make it difficult to couple THz radiation into accelerating structures. A better understanding of the THz near-field source properties is necessary for the optimization of THz transport and coupling. We have developed a technique for detailed measurement of the THz near-fields and used it to reconstruct the full temporal 3D THz near-field close to the LN emission face. Analysis of the results from this measurement will inform designs of novel structures for use in THz particle acceleration.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS015  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS016 Application of Nanostructures and Metamaterials in Accelerator Physics acceleration, wakefield, plasma, laser 659
 
  • J. Resta-López
    ICMUV, Paterna, Spain
  • Ö. Apsimon, C. Bonțoiu, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • A. Bonatto
    Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
  • B. Galante
    CERN, Meyrin, Switzerland
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • G.X. Xia
    UMAN, Manchester, United Kingdom
 
  Funding: This work is supported by the Generalitat Valenciana under Grant agreement No. CIDEGENT/2019/058.
Carbon-based nanostructures and metamaterials offer extraordinary mechanical and opto-electrical properties, which make them suitable for applications in diverse fields, including, for example, bioscience, energy technology and quantum computing. In the latest years, important R&D efforts have been made to investigate the potential use of graphene and carbon-nanotube (CNT) based structures to manipulate and accelerate particle beams. In the same way, the special interaction of graphene and CNTs with charged particles and electromagnetic radiation might open interesting possibilities for the design of compact coherent radiation sources, and novel beam diagnostics techniques as well. This paper gives an overview of novel concepts based on nanostructures and metamaterials with potential application in the field of accelerator physics. Several examples are shown and future prospects discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS016  
About • Received ※ 08 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 13 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS017 Beam Transport Simulations Through Final Focus High Energy Transport Lines with Implemented Gabor Lenses focusing, simulation, target, proton 663
 
  • A. Sherjan, M. Droba, O. Meusel, S. Reimann, K.I. Thoma
    IAP, Frankfurt am Main, Germany
  • S. Reimann
    GSI, Darmstadt, Germany
 
  First investigations on Gabor Lens GL2000 at Goethe University have shown that it is possible to confine a 2m long stable Electron Plasma Column and to apply it as a hadron beam focusing device. With this knowledge theoretical implementations of GLs in final focus and transfer lines have started. The focusing with GLs is a weak but smooth focusing in radial direction. The GL is a suitable and inexpensive choice in addition to the existing focusing elements eg. magnetic quadrupoles. The device helps to improve beam quality and minimize losses over long distances. The investigation of relativistic hadron beams in GeV range using the example of the proposed NA61/SHINE VLE-beamline at CERN is carried out and will be presented. Thin-matrix simulations with a generated distribution as well as field map simulations with generated and realistic distributions (Geant4) at 1 - 6 GeV/c have been analysed and compared. In addition, the H4-beamline at North Area (CERN) is proposed to implement GLs for experimental tests.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS017  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 14 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS018 Tungsten Electron Emitter (TE²) with Direct Heated Cathode by Plasma Stream cathode, plasma, gun, ion-source 667
 
  • K.I. Thoma, M. Droba, T. Dönges, O. Meusel, H. Podlech, K. Schulte-Urlichs
    IAP, Frankfurt am Main, Germany
  • K. Schulte-Urlichs, K.I. Thoma
    GSI, Darmstadt, Germany
 
  At Goethe-University, a novel concept of heating metallic cathodes is currently under investigation. In the scope of the ARIES collaboration WP16, an RF-modulated electron gun was developed and manufactured for application in electron lenses for space charge compensation. The goal of this project is to increase the intensity of primary beams, especially in low energy booster synchrotrons like the SIS18 and SIS100 at GSI/FAIR or the SPS at CERN. The gun was designed to produce electron currents of 10 A at extraction voltages of 30 kV. The tungsten electron emitter (TE²) and the grid electrode were designed and manufactured to be integrated in the extractor of the original volume type ion source. Significant effort was put into a robust and flexible design with highly reliable key components. The cathode is heated by a plasma stream generated in the plasma chamber of the source. Different heating options of the cathode are currently being studied. This contribution presents the working principles of the electron gun and first measurements results of cathode heating.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS018  
About • Received ※ 18 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS020 Dark Current Studies for a High Gradient SW C-Band RF Gun gun, cathode, simulation, solenoid 675
 
  • F. Cardelli, D. Alesini, L. Faillace, A. Giribono, A. Vannozzi
    INFN/LNF, Frascati, Italy
  • G. Di Raddo
    LNF-INFN, Frascati, Italy
  • T.G. Lucas
    PSI, Villigen PSI, Switzerland
 
  It is now well-established that for the generation of very high brightness beams, required for fourth generation light sources, it is highly advantageous to use injectors based on Radiofrequency photo-guns with very high peak electric fields on the cathode (>120 MV/m). This very high surface electric field leads to the generation of undesirable electrons due to the field emission effect. The emitted electrons can be captured and propagate along the Linac forming a dark current beam, leading to background radiation that can damage the instrumentation and radioactivate components. Consequently, it is important that the emission of these electrons, and their subsequent transportation, is carefully evaluated. Recently, in the framework of the I-FAST project, a high gradient, standing wave, C-band (5712 MHz) RF photogun has been designed and will be realized soon. In this paper, the results of dark current studies and simulations are illustrated. The transport efficiency and the spectrum of the dark current have been evaluated by Particle-In-Cell simulations for different cathode peak field values considering also the effect of the focusing solenoid on the dark current beam.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS020  
About • Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS022 Studies of a Ka-Band High Power Klystron Amplifier at INFN-LNF klystron, cavity, gun, focusing 683
 
  • M. Behtouei, L. Faillace, A. Mostacci, B. Spataro
    LNF-INFN, Frascati, Italy
  • F. Bosco, M. Carillo, M. Migliorati, A. Mostacci, L. Palumbo
    Sapienza University of Rome, Rome, Italy
  • F. Di Paolo, S. Fantauzzi, A. Leggieri, F. Marrese, L. Valletti
    Università degli Studi di Roma "Tor Vergata", Roma, Italy
  • G. Torrisi
    INFN/LNS, Catania, Italy
 
  In the framework of the Compact Light XLS project, a Ka-band linearizer with electric field ranging from 100 to 150 MV/m is requested. In order to feed this structure, a proper Ka-band high power klystron amplifier with a high efficiency is needed. This paper reports a possible solution for a klystron amplifier operating on the TM010 mode at 36 GHz, the third harmonic of the 12 GHz linac frequency, with an efficiency of 44% and 10.6 MW radiofrequency output power. We discuss also here the high-power DC gun with the related magnetic focusing system, the RF beam dynamics and finally the multiphysics analysis of a high- power microwave window for a Ka-band klystron providing 16MW of peak power.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS022  
About • Received ※ 18 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS023 Start-to-End Beam-Dynamics Simulations of a Compact C-Band Electron Beam Source for High Spectral Brilliance Applications simulation, FEL, laser, photon 687
 
  • L. Faillace, M. Behtouei, B. Spataro, C. Vaccarezza
    LNF-INFN, Frascati, Italy
  • R.B. Agustsson, I.I. Gadjev, S.V. Kutsaev, A.Y. Murokh
    RadiaBeam, Santa Monica, California, USA
  • F. Bosco, M. Carillo, L. Giuliano, M. Migliorati, A. Mostacci, L. Palumbo
    Sapienza University of Rome, Rome, Italy
  • D.L. Bruhwiler
    RadiaSoft LLC, Boulder, Colorado, USA
  • O. Camacho, A. Fukasawa, N. Majernik, J.B. Rosenzweig, O. Williams
    UCLA, Los Angeles, USA
  • A. Giribono
    INFN/LNF, Frascati, Italy
  • S.G. Tantawi
    SLAC, Menlo Park, California, USA
 
  Funding: This work is partially supported by DARPA under the Contract No. HR001120C0072, by DOE Contract DE-SC0009914, DOE Contract DE-SC0020409, and by the National Science Foundation Grant No. PHY-1549132.
Proposals for new linear accelerator-based facilities are flourishing world-wide with the aim of high spectral brilliance radiation sources. Most of these accelerators are based on electron beams, with a variety of applications in industry, research and medicine such as colliders, free-electron lasers, wake-field accelerators, coherent THz and inverse Compton scattering X/’ sources as well as high-resolution diagnostics tools in biomedical science. In order to obtain high-quality electron beams in a small footprint, we present the optimization design of a C-band linear accelerator machine. Driven by a novel compact C-band hybrid photoinjector, it will yield ultra-short electron bunches of few 100’s pC directly from injection with ultra-low emittance, fraction of mm-mrad, and a few hundred fs length simultaneously, therefore satisfying full 6D emittance compensation. The normal-conducting linacs are based on a novel high-efficiency design with gradients up to 50 MV/m. The beam maximum energy can be easily adjusted in the mid-GeV’s range. In this paper, we discuss the start-to-end beam-dynamics simulations in details.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS023  
About • Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS025 Photocathode Performance Characterisation of Ultra-Thin MgO Films on Polycrystalline Copper cathode, experiment, emittance, photon 691
 
  • C. Benjamin, H.M. Churn, L.B. Jones, T.C.Q. Noakes
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • G.R. Bell, C. Benjamin, T.J. Rehaag
    University of Warwick, Coventry, United Kingdom
  • H.M. Churn, L.B. Jones, T.C.Q. Noakes
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  Funding: Department of Physics, The University of Warwick, Coventry, United Kingdom STFC ASTeC, Daresbury, Warrington, United Kingdom WA4 4AD
The performance expected from the next generation of electron accelerators is driving research into photocathode technology as this fundamentally limits the achievable beam quality. The performance characteristics of a photocathode are most notably; normalised emittance, brightness and energy spread*. Ultra–thin Oxide films on metal substrates have been shown to lower the work function (WF) of the surface, enhancing commonly utilised metal photocathodes, potentially improving lifetime and performance characteristics**. We present the characterisation of two MgO/Cu photocathodes grown at Daresbury. The surface properties such as; surface roughness, elemental composition and WF, have been studied using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). The photoemissive properties have been characterised with quantum efficiency (QE) measurements at 266 nm. Additionally, we measure the Transverse Energy Distribution Curves (TEDC) for these photocathodes under illumination at various wavelengths using ASTeC’s Transverse Energy Spread Spectrometer (TESS) and extract the Mean Transverse Energy (MTE)***.
*D.H. Dowell, et al, Nucl. Instr. and Meth A (2010), doi:10.1016/j.nima.2010.03.104
**V. Chang, et al, Phys. Rev. B (2018), doi.org/10.1103/PhysRevB.97.155436
***Proc. FEL ’13, TUPPS033, 290-293
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS025  
About • Received ※ 19 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS027 Synthesis of First Caesium Telluride Photocathode at ASTeC Using Sequential and Co-Deposition Method cathode, target, site, FEL 695
 
  • R. Valizadeh, A.N. Hannah
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • V.R. Dhanak
    The University of Liverpool, Liverpool, United Kingdom
  • S. Lederer
    DESY, Hamburg, Germany
 
  Caesium Telluride (Cs2Te) photocathodes, are the elec-tron source of choice, by many global accelerators such as European XFEL, FLASH and AWA. It offers high quantum efficiency and reasonable operational lifetime with lower vacuum requirements than multi-alkali photocathodes. In this paper, we report on the first synthesised CsxTe photocathodes at ASTeC, using both sequential and co-deposition of Te and Cs on Mo substrate. Te deposition is carried out using ion beam deposition whilst the Cs is deposited using a SAES getter alkali. The ion beam deposition of Te provides a high degree of control to give a dense, smooth layer with a reproducible film thickness. The chemical state with respect to film composition of the deposited CsxTe is determined with in-situ XPS anal-yses. The films exhibit a quantum efficiency between 7.5 to 9 % at 266 nm wavelength.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS027  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS028 Stability and Lifetime Studies of Carbon Nanotubes for Electron Cooling in ELENA cathode, proton, antiproton, gun 699
 
  • B. Galante, G. Tranquille
    CERN, Meyrin, Switzerland
  • J. Resta-López, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • J. Resta-López, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • J. Resta-López
    ICMUV, Paterna, Spain
 
  Funding: Work supported by EU Horizon 2020 research and innovation programme under the Marie Sk’odowska-Curie grant agreement No 721559.
Electron cooling is a fundamental process to guarantee beam quality in low energy antimatter facilities. In ELENA, the electron cooler reduces the emittance blow-up of the antiproton beam so that a focused and bright beam can be delivered to the experiments at the unprecedentedly low energy of 100 keV. To achieve a cold beam at this low energy, the electron gun must emit a monoenergetic and relatively intense electron beam. An optimization of the electron gun involving a cold cathode is studied to investigate the feasibility of using carbon nanotubes (CNTs) as cold electron field emitters. CNTs are considered among the most promising field emitting materials. However, stability data for emission over hundreds of hours, as well as lifetime and conditioning process studies to ensure optimal performance, are still incomplete or missing, especially if the aim is to use them in operation. This contribution reports experiments that characterize these properties and assess whether CNTs are suitable to be used as cold electron field emitters for many hundreds of hours.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS028  
About • Received ※ 20 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS029 HPC Modeling of a High-Gradient C-Band Linac for Hard X-Ray Free-Electron Lasers simulation, cavity, FEL, linac 703
 
  • T.B. Bolin, S. Biedron
    UNM-ECE, Albuquerque, USA
  • S. Sosa
    ODU, Norfolk, Virginia, USA
 
  The production of soft to hard x-rays (up to 25 keV) at XFEL (x-ray free-electron laser) facilities has enabled new developments in a broad range of disciplines. Great potential exists for new scientific discovery at higher energies (42+ keV) such as envisioned at MaRIE (Matter-Radiation Interactions in Extremes) at Los Alamos National Laboratory. These instruments can require a large amount of real estate, which quickly escalates costs: The driver of the FEL is typically an electron beam linear accelerator (LINAC) and the need for higher beam energies capable of generating these X-rays can dictate that the linac becomes longer. State of art accelerating technology is required to reduce the linac length by reducing the size of the cavities, providing for compact, high-frequency, high acceleration gradients. Here, we describe using the Argonne Leadership Computing Facility (ALCF) to facilitate our investigations into design concepts for future XFEL high-gradient LINAC’s in the C-band (~4-8 GHz). We investigate two different traveling wave (TW) geometries optimized for high-gradient operation as modeled at the ALCF using VSim software.*
* https://www.txcorp.com
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS029  
About • Received ※ 03 July 2022 — Accepted ※ 04 July 2022 — Issue date ※ 08 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS032 Compact-Two-Octave-Spanning Perpendicular Kicker of MeV Electrons Based on a Cubic Magnet Dipole Array dipole, radiation, laser, kicker 706
 
  • T. Rohwer, R. Bazrafshan, F.X. Kärtner, N.H. Matlis
    Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
  • R. Bazrafshan
    University of Hamburg, Hamburg, Germany
  • F.X. Kärtner
    The Hamburg Center for Ultrafast Imaging, University of Hamburg, Hamburg, Germany
  • F.X. Kärtner
    CFEL, Hamburg, Germany
  • P. Vagin
    DESY, Hamburg, Germany
 
  Funding: This work has been supported by the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) through the Synergy Grant AXSIS (609920).
New compact particle acceleration structures, including but not limited to plasma, THz and direct laser driven accelerators, have in common that they cover a wide energy range of potential final energies and often show a large energy spread. Moreover, they may initially have a rather large emittance. To analyze the energy range of a single shot and/or to deflect the beam to safely dump the electrons away from an end-station requires an electron kicker covering a large energy range. Here, we present a magnetic dipole structure based on a 2D Halbach array. For the current experimental test accelerator in AXSIS, an electron beam in the energy range from 4 to 20 MeV is deflected by 90 degree and energetically dispersed. In direct contrast to a simple magnetic dipole, an array of cubic magnet blocks with tailored magnetization directions allows a focusing of the beam for both longitudinal and transverse directions at 90 degree bend. A generic algorithm optimizes the magnetic field array to the predefined deflection angle and divergence. The modular array structure, in combination with the algorithm enables a simple exchange of magnets to adapt for different beam parameters.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS032  
About • Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 14 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS033 Emittance Measurements of Nanoblade-Enhanced High Field Cathode cathode, simulation, emittance, laser 709
 
  • G.E. Lawler, N. Majernik, J.I. Mann, N.E. Montanez, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • V.S. Yu
    RadiaBeam, Santa Monica, California, USA
 
  Funding: This work was supported by the Center for Bright Beams, National Science Foundation Grant No. PHY-1549132.
High brightness cathodes are increasingly a focus for accelerator applications ranging from free electron lasers to ultrafast electron diffraction. There is further an increasing interest in fabrication and control of cathode surface to better control the emission characteristics and improve beam brightness. One method which we can consider is based on well-known silicon nanofabrication techniques which we use to create patterned cathode surfaces. The sharp edges produced lead to field emission increases and high brightness emission. We have demonstrated that a beam can be successfully extracted with a low emittance and we have reconstructed a portion of the energy spectrum. Due to the simplicity of extended geometries in nanofabrication our beam uniquely possesses a high aspect ratio in its transverse cross section. We can begin to consider modifications for emittance exchange beamlines and having shown the patterning principle is sound we can consider additional patterns such as hollow beams. Future work will continue to characterize the produced beam and the addition of fabrication steps to remove one of the blades in the double blade geometry in order to more accurately characterize the emission.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS033  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS034 Material Normal Energy Distribution for Field Emission Analyses From Monocrystalline Surfaces vacuum, lattice, framework, cathode 713
 
  • J.I. Mann, Y. Li, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • T. Arias, J.K. Nangoi
    Cornell University, Ithaca, New York, USA
 
  Funding: National Science Foundation Grant No. PHY-1549132
Electron field emission is a complicated phenomenon which is sensitive not only to the particular material under illumination but also to the specific crystalline orientation of the surface. Summarizing the ability for a crystal to emit in a particular direction would be of great use when searching for good field emitters. In this paper we propose a material normal energy distribution which describes the ability of the bound electrons to tunnel under an intense electric field. This framework breaks a computationally expensive 3-D system down to a source distribution representation applicable for more efficient 1-D models. We use the Fowler-Nordheim framework to study the yield and MTE (mean transverse energy) from sources including gold, copper, and tungsten in both monocrystalline and polycrystalline forms. We find an increase in effective work function for field emission in the (111) direction for gold and copper associated with the Bragg plane intersections of the Fermi surface.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS034  
About • Received ※ 20 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS036 Simulations of Laser Field Emission from Nanostructures with Image Charge Trapping and Band Structure Transitions laser, simulation, vacuum, photon 717
 
  • B. Wang, G.E. Lawler, J.I. Mann, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • T. Arias, J.K. Nangoi
    Cornell University, Ithaca, New York, USA
  • S.S. Karkare
    Arizona State University, Tempe, USA
 
  Funding: National Science Foundation Grant No. PHY-1549132
Laser-induced field emission from nanostructures as a means to create high brightness electron beams has been a continually growing topic of study. Experiments using nanoblade emitters have achieved peak fields upwards of 40 GV/m, begging further investigation in this extreme regime. A recent paper has provided analytical reductions of the common semi-infinite Jellium system for pulsed incident lasers. We utilize these results as well as similar previous results to further understand the physics underlying electron rescattering-type emissions. We progress in numerically evaluating the analytical solution to attempt to more efficiently generate spectra for this system. Additionally, we use the full 1-D time-dependent Schrödinger equation with a Hartree potential and a dispersion-relation transition from material to vacuum to study the same system. We determine what importance the inclusion of the material band structure may have on emissions using this computationally challenging approach.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS036  
About • Received ※ 08 June 2022 — Revised ※ 21 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS039 Study of Material Choice in Beam Dumps for Energetic Electron Beams target, linac, neutron, scattering 721
 
  • D. Zhu, R.T. Dowd, Y.E. Tan
    AS - ANSTO, Clayton, Australia
 
  Lead is typically used as the initial target in a design for beam dumps for high energy electron beams (>20 MeV). Electron beams with energies above 20 MeV are usually built within concrete bunkers and therefore the design of any beam dump would just be a lead block (very cost effective) as close to the electron source as possible, after a vacuum flange of some sort. In a study of a hypothetical 100 MeV electron beam inside a concrete bunker with an extremely low dose rate constraint outside the bunker, the thickness of lead required would have been too restrictive for a compact design. In this study we investigate the potential benefits of designs that incorpo-rate low Z materials like graphite as the primary target material in vacuum followed by progressively higher Z materials up to lead. The results show the more diffuse elastic scattering from the primary target reduces the back scattered photons and reduces the overall neutron genera-tion. The effect was a more compact design for the beam dump to meet the same dose rate constraint.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS039  
About • Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS040 Radiation Shielding Design for the X-Band Laboratory for Radio-Frequency Test Facility - X-Lab - at the University of Melbourne radiation, controls, simulation, operation 724
 
  • M. Volpi, R.P. Rassool, S.L. Sheehy, G. Taylor, S.D. Williams
    The University of Melbourne, Melbourne, Victoria, Australia
  • D. Banon-Caballero
    IFIC, Valencia, Spain
  • M. Boronat, N. Catalán Lasheras
    CERN, Meyrin, Switzerland
  • R.T. Dowd
    AS - ANSTO, Clayton, Australia
  • S.L. Sheehy
    ANSTO, Kirrawee DC New South Wales, Australia
 
  Here we report radiation dose estimates calculated for the X-band Laboratory for Accelerators and Beams (X-LAB) under construction at the University of Melbourne (UoM). The lab will host a CERN X-band test stand containing two 12 GHz 6 MW klystron amplifiers. By power combination through hybrid couplers and the use of pulse compressors, up to 50 MW of peak power can be sent to any of to either of the two test slots at pulse repetition rates up to 400 Hz. The test stand is dedicated to RF conditioning and testing CLIC’s high gradient accelerating structures beyond 100 MV/m. This paper also gives a brief overview of the general principles of radiation protection legislation; explains radiological quantities and units, including some basic facts about radioactivity and the biological effects of radiation; and gives an overview of the classification of radiological areas at X-LAB, radiation fields at high-energy accelerators, and the radiation monitoring system used at X-LAB. The bunker design to achieve a dose rate less than annual dose limit of 1 mSv is also shown.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS040  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS044 Implications and Mitigation of Radiation Effects on the CERN SPS Operation during 2021 radiation, shielding, electronics, operation 740
 
  • Y.Q. Aguiar, A. Apollonio, K. Biłko, M. Brucoli, M. Cecchetto, S. Danzeca, R. García Alía, T. Ladzinski, G. Lerner, J.B. Potoine, A. Zimmaro
    CERN, Meyrin, Switzerland
 
  During the Long Shutdown 2 (LS2, 2019-2020), the CERN accelerator complex has undergone major upgrades, mainly in preparation for the High-Luminosity (HL) LHC era, the ultimate capacity for its physics production. Therefore, several novel equipment and systems were designed and deployed throughout the accelerator complex. To comply with the radiation level specifications and avoid machine downtime due to radiation effects, the electronics systems exposed to radiation need to follow Radiation Hardness Assurance (RHA) methodologies developed and validated by the Radiation to Electronics (R2E) project at CERN. However, the establishment of such procedures is not yet fully implemented in the LHC injector chain, and some R2E failures were detected in the SPS during the 2021 operation. This work is devoted to describing and analysing the R2E failures and their impact on operation, in the context of the related radiation levels and equipment sensitivity.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS044  
About • Received ※ 07 June 2022 — Revised ※ 21 June 2022 — Accepted ※ 26 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS050 Rigorous Approach for Calculation of Radiation of a Charged Particle Bunch Exiting an Open-Ended Dielectrically Loaded Waveguide GUI, radiation, wakefield, acceleration 757
 
  • S.N. Galyamin
    Saint Petersburg State University, Saint Petersburg, Russia
  • S. Baturin
    ITMO University, Saint Petersburg, Russia
 
  Funding: Work supported by Russian Science Foundation (Grant No. 18-72-10137).
Beam-driven radiation sources based on open-ended waveguide structures with dielectric filling are of essential interest due to their attractive possibilities to generate high-power narrow-band Cherenkov radiation*. An important problem here is to effectively extract the radiation from the waveguide to the open space. Therefore, further development of this scheme requires rigorous mathematical approach describing the interaction of both charged particle bunch and produced radiation with the open end of a waveguide. In this report, we present the corresponding analytical approach based on our recent paper** where diffraction of a waveguide mode at the open end of a dielectrically loaded waveguide has been rigorously investigated.
* D. Wang et al., Rev. Sci. Instruments, Vol. 89, 093301 (2018).
** S.N. Galyamin et al., IEEE Trans. Microwave Theory Techn., Vol. 69, 2429-2438 (2021).
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS050  
About • Received ※ 09 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPOMS052 6 MeV Novel Hybrid (Standing Wave - Traveling Wave) Photo-Cathode Electron Gun for a THz Superradiant FEL gun, cathode, klystron, experiment 760
 
  • A. Nause, L. Feigin, A. Friedman, A. Weinberg
    Ariel University, Ariel, Israel
  • A. Fukasawa, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • B. Spataro
    LNF-INFN, Frascati, Italy
 
  A novel 6 MeV hybrid photo injector was designed and commissioned at Ariel University in Israel as an on-going collaboration with UCLA. This unique, new generation design provides a radically simpler approach to RF feeding of a gun/buncher system, leading to a much shorter beam via velocity bunching owed to an attached traveling wave section of the photo-injector. This design results in better performance in beam parameters, providing a high quality electron beam, with energy of 6 MeV, emittance of less than 3 ’m, and a 150 fs pulse duration at up to 1 nC per pulse. The Hybrid gun is driven by a SLAC XK5 Klystron as the high power RF source, and third harmonic of a fs level IR Laser amplifier (266 nm) to extract electrons from the Cathode. The unique e-gun will produce a bunched electron pulse to drive a THz FEL, which will operate at the super-radiance regime, and therefore requires extraordinary beam properties. It will also be used for MeV UED experiments in a separate line using a dogleg section. Here we describe the gun and presents experimental results from the gun and its sub-systems, including energy and charge measurements, compared with the design simulations.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS052  
About • Received ※ 11 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 18 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUOXGD1 Design and Construction of Optical System of the Coronagraph for Beam Halo Observation in the SuperKEKB radiation, scattering, synchrotron, synchrotron-radiation 769
 
  • G. Mitsuka, H. Ikeda, T.M. Mitsuhashi
    KEK, Ibaraki, Japan
 
  For the observation of beam halo, the coronagraph is designed and constructed in the SuperKEKB. The coronagraph has three stages of optical systems, objective system, re-diffraction system and relay system. Since the SR monitor of SuperKEKB has a long optical path (60 m), we need an objective system with long focal length. The Aperture limit is determined by the diamond mirror which is set in 23.6 m from the source point. Therefore, we must assign this aperture for the entrance pupil of the objective system. For satisfying these conditions, we design a reflective telephoto system based on the Gregorian telescope for the objective system. The focal length is designed to 7028 mm. and front principal point position is designed to the position of diamond mirror. The result of construction, the performance of the objective system has a diffraction limited quality. The re-diffraction system and relay system are also designed based on Kepler type telescope. The result of optical testing using the beam in the HER, we achieved a contrast of 6 order magnitude. Some early result for the observation of beam halo in the HER will also present in this presentation.  
slides icon Slides TUOXGD1 [4.345 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOXGD1  
About • Received ※ 09 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUOXGD2 Wireless IoT in Particle Accelerators: A Proof of Concept with the IoT Radiation Monitor at CERN radiation, network, monitoring, electronics 772
 
  • S. Danzeca, A.J. Cass, A. Masi, R. Sierra, A. Zimmaro
    CERN, Meyrin, Switzerland
 
  The Internet of Things (IoT) is an ecosystem of web-enabled "smart devices" that integrates sensors and communication hardware to collect, send and act on data acquired from the surrounding environment. Use of the IoT in particle accelerators is not new, with accelerator systems long having been connected to the network to retrieve, send and analyse data. What has been missing is the IoT concept of "smart devices" and above all wireless connectivity. We report here on the advantages of using a particular IoT technology, LoRa, for the deployment of wireless radiation monitors within the CERN particle accelerator complex. IoT Radiation Monitors have been developed as a result of growing demand for radiation measurements where standard infrastructure is not available. As a radiation-tolerant device, the IoT Radiation Monitor is a powerful "eye" for observing the real-time radiation levels in the CERN accelerators. We describe here the technologies used for the project and the various advantages their deployment offers in a particle accelerator environment. This opens up the possibility for the deployment of heterogeneous implementations that would otherwise have been impractical.  
slides icon Slides TUOXGD2 [5.797 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOXGD2  
About • Received ※ 07 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUOXSP1 Origin and Mitigation of the Beam-Induced Surface Modifications of the LHC Beam Screens radiation, cryogenics, ECR, MMI 780
 
  • V. Petit, P. Chiggiato, M. Himmerlich, S. Marinoni, H. Neupert, M. Taborelli, L.J. Tavian
    CERN, Meyrin, Switzerland
 
  All over Run 2, the LHC beam-induced heat load on the cryogenic system exhibited a wide scattering along the ring. Studies ascribed the heat source to electron cloud build-up, indicating an unexpected high Secondary Electron Yield (SEY) of the beam screen surface in some LHC regions. The inner copper surface of high and low heat load beam screens, extracted during the Long Shutdown 2, was analysed. On the low heat load ones, the surface was covered with the native Cu2O oxide, while on the high heat load ones CuO dominated at surface, and it exhibited a very low carbon coverage. Such chemical modifications increase the SEY and inhibit a proper conditioning of the affected surfaces. Following this characterisation, the mechanisms for CuO build-up in the LHC beam pipe were investigated on a newly commissioned cryogenic system allowing electron irradiation, surface chemical characterisation by X-ray Photoelectron Spectroscopy and SEY measurements on samples held below 15 K. In parallel, curative solutions against the presence of CuO in the LHC beam screens were explored, which could be implemented in-situ to recover a proper conditioning and lower the beam-induced heat load.  
slides icon Slides TUOXSP1 [2.669 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOXSP1  
About • Received ※ 17 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUOZSP3 The European ERL Roadmap gun, FEL, linac, SRF 831
 
  • A. Hutton
    JLab, Newport News, Virginia, USA
  • M. Klein
    The University of Liverpool, Liverpool, United Kingdom
  • B.C. Kuske
    HZB, Berlin, Germany
 
  Funding: AH supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Contract No. DE-AC05-06OR23177
Following the European Strategy process in 2019, five Roadmap Panels were set up to prepare the technologies needed for future accelerators and colliders: high-field magnets, SRF, muon colliders, plasma wakefield accelerators and Energy Recovery Linacs (ERLs). The ERL Roadmap Panel, consisting of ERL experts from around the world, first developed an overview of current and future ERLs. From this it was possible to carry out a gap analysis to see what R&D would be needed, from which the Roadmap could be developed. The European ERL Roadmap focused on three main aspects: 1) the continuation and development of facility programs for which no additional funds are needed, S-DALINAC in Darmstadt and MESA in Mainz; 2) technology development for room-temperature HOM damping and twin-axis SRF cavities; 3) the timely upgrade of bERLinPro for 100 mA current and the construction of PERLE at Orsay as a dedicated 10 MW power multi-turn facility. The roadmap entails a vision of future energy frontier electron-positron and electron-hadron collider and describes a high quality ERL program for 4.4 K SRF technology at high Q0. The presentation will address the ERL Roadmap process and result in detail.
 
slides icon Slides TUOZSP3 [2.868 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOZSP3  
About • Received ※ 02 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST001 Parasitic Optimization of the Transfer Beamline Efficiency at ELSA target, synchrotron, injection, controls 835
 
  • S. Witt, K. Desch, D. Elsner, D. Proft
    ELSA, Bonn, Germany
 
  The 3.2 GeV electron accelerator ELSA in Bonn consists of three acceleration stages each interconnected by tunable transfer beamlines. The steering of the electron beam through the transfer line from linear accelerator to the Booster Synchrotron is currently adjusted by hand, which limits a systematic improvement of the transfer efficiency. An automated optimization using the ‘‘simulated annealing’’ technique has been developed and integrated into the control system to improve the situation. It allows for a continuous optimization without interfering with usual beamtime for experiments by utilizing the 6s off-time in between injections into the stretcher ring. In a simulation using the actual accelerator’s settings as starting parameters, transmission rates have been increased significantly. The methods and results with the accelerator hardware are presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST001  
About • Received ※ 06 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST002 Upgrade of the 25 MW RF Station for the Linear Accelerator LINAC2 at ELSA klystron, linac, monitoring, GUI 838
 
  • D. Proft, K. Desch, D. Elsner, M.T. Switka
    ELSA, Bonn, Germany
 
  At the Electron Stretcher Facility ELSA in Bonn the first acceleration stage consists of a 3 GHz traveling wave linear accelerator. It was powered by a 25 MW pulsed high power klystron amplifier, which had been in use for the last thirty years. After a major failure and due to the lack of spare part availability the RF station was rebuilt. In addition to a new klystron including its high voltage tank, the new setup also consists of major upgrades of the infrastructure, the pulse forming network and the safety interlocks to satisfy the contemporary requirements. A new monitoring system consisting of multi-channel sampling ADCs allows for automatic pulse-by-pulse analysis of the klystron parameters and simultaneous evaluation of RF performance and stability. In this contribution we will present the new RF station setup, which has successfully been operating since the beginning of 2021 as well as the new monitoring capabilities.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST002  
About • Received ※ 04 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST009 Online Correction of Laser Focal Position Using FPGA-Based ML Models laser, network, FPGA, controls 857
 
  • J.A. Einstein-Curtis, S.J. Coleman, N.M. Cook, J.P. Edelen
    RadiaSoft LLC, Boulder, Colorado, USA
  • S.K. Barber, C.E. Berger, J. van Tilborg
    LBNL, Berkeley, California, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics under Award Numbers DE-SC 00259037 and DE-AC02-05CH11231.
High repetition-rate, ultrafast laser systems play a critical role in a host of modern scientific and industrial applications. We present a prototype diagnostic and correction scheme for controlling and determining laser focal position at 10 s of Hz rate by utilizing fast wavefront sensor measurements from multiple positions to train a focal position predictor. This predictor is used to determine corrections for actuators along the beamline to provide the desired correction to the focal position on millisecond timescales. Our initial proof-of-principle demonstrations leverage pre-compiled data and pre-trained networks operating ex-situ from the laser system. We then discuss the application of a high-level synthesis framework for generating a low-level hardware description of ML-based correction algorithms on FPGA hardware coupled directly to the beamline. Lastly, we consider the use of remote computing resources, such as the Sirepo scientific framework* , to actively update these correction schemes and deploy models to a production environment.
* M.S. Rakitin et al., "Sirepo: an open-source cloud-based software interface for X-ray source and optics simulations", Journal of Synchrotron Radiation 25, 1877-1892 (Nov 2018).
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST009  
About • Received ※ 20 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST017 PEG Contribution to the LLRF System for Superconducting Elliptical Cavities of ESS Accelerator Linac LLRF, cavity, controls, hardware 884
 
  • W. Cichalewski, G.W. Jabłoński, K. Klys, D.R. Makowski, A. Mielczarek, A. Napieralski, P. Perek, P. Plewinski
    TUL-DMCS, Łódź, Poland
  • A. Abramowicz, K. Czuba, M.G. Grzegrzółka, K. Oliwa, I. Rutkowski, W. Wierba
    Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
  • P.R. Bartoszek, K. Chmielewski, K. Kostrzewa, T. Kowalski, D. Rybka, M. Sitek, J. Szewiński, Z. Wojciechowski
    NCBJ, Świerk/Otwock, Poland
  • M. Jensen
    ESS, Lund, Sweden
  • A.J. Johansson, A.M. Svensson
    Lund University, Lund, Sweden
 
  The LLRF (Low-Level Radio Frequency) system optimizes energy transfer from the superconducting resonator to the accelerating beam. At ESS, one LLRF system regulates a single cavity. This digital system’s HW platform is the MTCA.4 standard. The system has been co-designed by ESS, Lund University, and the PEG (Polish Electronic Group) consortium. The PEG is also responsible for the system components design, evaluation, and production (like Local Oscillator Rear transition module, piezo tuner driver RTM, RTM carrier board, and others). The PEG delivers a HW/SW cavity simulator, an LLRF system test-stand, and provides necessary integration and installation services required for complete system preparation for the linac commissioning and operation phase. The paper summarizes the PEG work on the development and preparation of the LLRF systems for the ESS elliptical structures. The efforts concerning hardware and software components prototyping and evaluation are discussed. Moreover, we present the current status of the project, including components mass production, integration, and installation work.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST017  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 19 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST040 Automated Intensity Optimisation Using Reinforcement Learning at LEIR linac, target, injection, operation 941
 
  • N. Madysa, R. Alemany-Fernández, N. Biancacci, B. Goddard, V. Kain, F.M. Velotti
    CERN, Meyrin, Switzerland
 
  High intensities in the CERN Low Energy Ion Ring (LEIR) are achieved by stacking up to seven consecutive multi-turn injections from Linac3. Two inclined septa combined with a collapsing horizontal orbit bump allow a 6-D phase space painting via a linearly ramped mean momentum along the Linac3 pulse and injection at high dispersion. The beam is cooled and dragged longitudinally via electron cooling (e-cooling) into a stacking momentum. For optimal accumulation, the electron energy and trajectory need to match the ion energy and orbit at the e-cooler section. In this paper, a reinforcement learning (RL) agent is trained to adjust various e-cooler and Linac3 parameters to maximise the intensity at the end of the injection plateau. Variational Auto-Encoders (VAE) are used to compress longitudinal Schottky spectra into a compact representation as input for the RL agent. The RL agent is pre-trained on a surrogate model of the LEIR e-cooling dynamics, which in turn is learned from the data collected for the training of the VAE. The performance of the VAE, the surrogate model, and the RL agent is investigated in this paper. An overview of planned tests in the upcoming LEIR runs is given.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST040  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST049 Simulation Study for an Inverse Designed Narrowband THz Radiator for Ultrarelativistic Electrons radiation, simulation, experiment, photon 973
 
  • G. Yadav, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • T. Feurer
    Universität Bern, Institute of Applied Physics, Bern, Switzerland
  • U. Haeusler, A. Kirchner
    FAU, Erlangen, Germany
  • B. Hermann, R. Ischebeck
    PSI, Villigen PSI, Switzerland
  • P. Hommelhoff
    University of Erlangen-Nuremberg, Erlangen, Germany
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  THz radiation has many applications, including medical physics, pump-probe experiments, communications, and security systems. Dielectric grating structures can be used to generate cost-effective and beam synchronous THz radiation based on the Smith Purcell effect. We present a 3-D finite difference time domain (FDTD) simulation study for the THz radiation emitted from an inverse designed grating structure after a 3 GeV electron bunch traverses through it. Our farfield simulation results show a narrowband emission spectrum centred around 881 um, close to the designed value of 900 um. The grating structure was experimentally tested at the SwissFEL facility, and our simulated spectrum shows good agreement with the observed one.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST049  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 12 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST050 Liverpool Centre for Doctoral Training for Innovation in Data Intensive Science cathode, simulation, experiment, network 976
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: This new Center for Doctoral Training has received funding from the UK’s Science and Technology Facilities Council.
The Liverpool center for doctoral training for innovation in data intensive science (LIV. INNO) is an inclusive hub for training three cohorts of students in data intensive science. Starting in October 2022, each year will train about 12 PhD students in applying data skills to address cutting edge research challenges across astrophysics, nuclear, theoretical and particle physics, as well as accelerator science. This framework is expected to provide an ideal basis for driving science and innovation, as well as boosting the employability of the LIV. INNO PhD students. This contribution gives examples of the accelerator science R&D projects in the center. It includes details about research into the optimization of 3D imaging techniques and the characterization of photocathodes for accelerator applications.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST050  
About • Received ※ 05 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST051 Using Data Intensive Science for Accelerator Optimization plasma, experiment, simulation, radiation 980
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: This work was supported by STFC under grant agreement ST/P006752/1.
Particle accelerators and light sources are some of the largest, most data intensive, and most complex scientific systems. The connections and relations between machine subsystems are complicated and often nonlinear with system dynamics involving large parameter spaces that evolve over multiple relevant time scales and accelerator systems. In 2017, the Liverpool Centre for Doctoral Training in Data Intensive Science (LIV. DAT) was established. With almost 40 PhD students, the centre is now established as an international hub for training PhD students in data intensive science. This contribution presents results from studies carried out in LIV. DAT into novel high gradient accelerators with a focus on the data science techniques that were used. This includes studies into inverse-designed narrowband THz radiators for ultra-relativistic electrons, simulation of the transverse asymmetry and inhomogeneity on seeded self-modulation of beams in plasma, as well as studies into the physical aspects of collinear laser injection in Trojan Horse laser plasma experiments.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST051  
About • Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST054 Experiment of Bayesian Optimization for Trajectory Alignment at Low Energy RHIC Electron Cooler experiment, alignment, collider, controls 987
 
  • Y. Gao, K.A. Brown, X. Gu, J. Morris, S. Seletskiy
    BNL, Upton, New York, USA
  • J.A. Crittenden, G.H. Hoffstaetter, W. Lin
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  Funding: Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy; U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams.
As the world’s first electron cooler that uses radio frequency (rf) accelerated electron bunches, the low energy RHIC electron cooling (LEReC) system is a nonmagnetized cooler of ion beams in RHIC at Brookhaven National Laboratory. Beam dynamics in LEReC are different from the more conventional electron coolers due to the bunching of the electron beam. To ensure an efficient cooling performance at LEReC, many parameters need to be monitored and fine-tuned. The alignment of the electron and ion trajectories in the LEReC cooling sections is one of the most critical parameters. This work explores using a machine learning (ML) method - Bayesian Optimization (BO) to optimize the trajectories’ alignment. Experimental results demonstrate that ML methods such as BO can perform control tasks efficiently in the RHIC controls system.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST054  
About • Received ※ 04 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST055 Toward Machine Learning-Based Adaptive Control and Global Feedback for Compact Accelerators controls, feedback, diagnostics, quadrupole 991
 
  • F.W. Cropp V, P. Musumeci
    UCLA, Los Angeles, USA
  • D. Filippetto, A. Gilardi, S. Paiagua, D. Wang
    LBNL, Berkeley, California, USA
  • A. Scheinker
    LANL, Los Alamos, New Mexico, USA
 
  Funding: This work was supported by the DOE Office of Science Graduate Student Research (SCGSR) program, by the DOE Office of Basic Energy Sciences under Contract No. DE-AC02-05CH11231, … continued
The HiRES beamline at Lawrence Berkeley National Laboratory (USA) is a state-of-the-art compact accelerator providing ultrafast relativistic electron pulses at MHz repetition rates, for applications in ultrafast science and for particle accelerator science and technology R&D. Using HiRES as testbed, we seek to apply recent developments in machine learning and computational techniques for machine-learning-based adaptive control, and eventually, a full control system based on global feedback. The ultimate goal is to demonstrate the benefits of such a suite of controls to UED, including increased temporal and spatial resolution. Concrete steps toward these goals are presented, including automatic, model-independent tuning for accelerators, and energy virtual diagnostics with direct application to improving UED temporal resolution.
… [continued from below] by the DOE Office of Science, Office of High Energy Physics under contract number 89233218CNA000001 and DE-AC02-05CH11231 and by the NSF under Grant No. PHY-1549132.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST055  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOST056 Multi-Objective Bayesian Optimization at SLAC MeV-UED gun, controls, detector, timing 995
 
  • F. Ji, A.L. Edelen, R.J. England, P.L. Kramer, D. Luo, C.E. Mayes, M.P. Minitti, S.A. Miskovich, M. Mo, A.H. Reid, R.J. Roussel, X. Shen, X.J. Wang, S.P. Weathersby
    SLAC, Menlo Park, California, USA
 
  SLAC MeV-UED, part of the LCLS user facility, is a powerful ’electron camera’ for the study of ultrafast molecular structural dynamics and the coupling of electronic and atomic motions in a variety of material and chemical systems. The growing demand of scientific applications calls for rapid switching between different beamline configurations for delivering electron beams meeting specific user run requirements, necessitating fast online tuning strategies to reduce set up time. Here, we utilize multi-objective Bayesian optimization(MOBO) for fast searching the parameter space efficiently in a serialized manner, and mapping out the Pareto Front which gives the trade-offs between key beam parameters, i.e., spot size, q-resolution, pulse length, pulse charge, etc. Algorithm, model deployment and first test results will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST056  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 09 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT006 The New FLASH1 Beamline for the FLASH2020+ Project undulator, FEL, photon, dipole 1010
 
  • M. Vogt, J. Zemella
    DESY, Hamburg, Germany
 
  The 2nd stage of the FLASH2020+ project will be an upgrade of the FLASH1 beamline, downstream of the injector/linac section FLAH0 which is currently being upgraded. The currently existing beamline drives the original planar fixed gap SASE undulators from the TTF-2 setup, a THz undulator that uses the spent electron beam and deflects the e-beam into a dump beamline capable of safely dumping several thousand bunches per second. The updated beamline has been designed for EEHG seeding with 2 modulators, 3 chicanes, and a helical Apple-III undulator beamline as seeding radiator, followed by a transverse deflecting (S-band) structure for longitudinal diagnostics. The separation of the electron beam from the FEL beam will be moved upstream w.r.t. the old design to create more space for the photon diagnostics and will be achieved by a 5 deg double-bend-almost-achromat. To allow enable high power THz radiation output from a moderately compressed seeding beam, a post compressor will be installed. The capability of dumping the the long bunch trains safely may and will not be compromised by the design. This article describes the conceptional and some technical and details of the beamline.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT006  
About • Received ※ 07 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 23 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT008 An Overview of the T20 Beamline for the LUXE Experiment at the European XFEL FEL, emittance, experiment, linac 1014
 
  • S.D. Walker, N. Golubeva
    DESY, Hamburg, Germany
 
  The Laser Und XFEL Experiment (LUXE) at the EUXFEL aims to explore hitherto unprobed regions of quantum electrodynamics characterised by both high-energy and high-intensity. This will be accomplished by leveraging the electron beam provided by the EUXFEL and an intensely-focussed laser to study electron-photon and photon-photon interactions. The LUXE experiment will be placed in the empty XTD20 tunnel and to this end a new beamline, T20, will need to be installed to deliver one bunch per bunch train to LUXE. The T20 beamline feature a total bend angle of 6.7 degrees, which combined with the very short bunches provided by the EUXFEL raises concerns regarding the deleterious impact of of coherent synchrotron radiation (CSR) on the bunch emittances. As the LUXE experiment has specific beam size requirements at its IP, these effects and the limits on the focus must be characterised. In this paper the T20 beamline design and its final focus are outlined. Furthermore, the impact of collective effects on the beam quality at the LUXE IP are discussed, and finally a means to mitigate the impact of these effects and improve the beam quality at the LUXE IP is shown.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT008  
About • Received ※ 13 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 19 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT010 Virtual Commissioning of the European XFEL for Advanced User Experiments at Photon Energies Beyond 25 keV Using Low-Emittance Electron Beams FEL, photon, laser, free-electron-laser 1018
 
  • Y. Chen, F. Brinker, W. Decking, M. Scholz, L. Winkelmann, Z.H. Zhu
    DESY, Hamburg, Germany
 
  Funding: The authors acknowledge support from Deutsches Elektronen-Synchrotron DESY (Hamburg, Germany), a member of the Helmholtz Association HGF and European XFEL GmbH (Schenefeld, Germany).
Growing interests in ultra-hard X-rays are pushing forward the frontier of commissioning the European X-ray Free-Electron Laser (XFEL) for routine operation towards the sub-ångström regime, where a photon energy of 25 keV (0.5 ångström) is desired. Such X-rays allow for larger penetration depths and enable the investigation of materials in highly absorbing environments. Delivering the requested X-rays to user experiments is of crucial importance for the XFEL development. Unique capabilities of the European XFEL are formed by combining a high energy linac and the long variable-gap undulator systems for generating intense X-rays at 25 keV and pushing the limit even further to 30 keV. However, the FEL performance relies on achievable electron bunch qualities. Low-emittance electron bunch production, and the associated start-to-end modelling of beam physics thus becomes a prerequisite to dig into the XFEL potentials. Here, we present the obtained results from a virtual commissioning of the XFEL for the user experiments at 25 keV and beyond, including the optimized electron bunch qualities at variable accelerating cathode gradients and lasing studies under different conditions.
*Appl. Sci. 11(22), 10768 (2021)
**Phys. Rev. Accel. Beams 23, 044201(2020)
***NIM A 995, 11 165111 (2021)
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT010  
About • Received ※ 19 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT011 Start To End Simulation Study For Oscillator-Amplifier Free-Electron Laser radiation, simulation, FEL, cavity 1022
 
  • H. Sun, Z.H. Zhu
    SINAP, Shanghai, People’s Republic of China
  • C. Feng, B. Liu
    SARI-CAS, Pudong, Shanghai, People’s Republic of China
  • Z.H. Zhu
    DESY, Hamburg, Germany
 
  External seeding techniques like high-gain harmonic generation (HGHG) and echo-enabled harmonic generation (EEHG) have been proposed and proven to be able to generate fully coherent radiation in the EUV and X-ray range. A big challenge is to combine the advantages of seeding schemes with high repetition rates. Recently, for seeding at a high repetition rate, an optical resonator scheme has been introduced to recirculate the radiation in the modulator to seed the high repetition rate electron bunches. Earlier studies have shown that a resonator-like modulator combined with an amplifier in high gain harmonic generation (HGHG) configuration can be used to generate radiation whose wavelength can reach the water window region. This scheme overcomes the limitation of requiring high repetition rate seed laser systems. In this contribution, we present start-to-end simulation results of a seeded oscillator-amplifier FEL scheme.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT011  
About • Received ※ 07 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT013 Twin Delayed Deep Deterministic Policy Gradient for Free-electron Laser Online Optimization FEL, laser, network, undulator 1025
 
  • M. Cai, C. Feng, L. Tu, Z.T. Zhao, Z.H. Zhu
    SINAP, Shanghai, People’s Republic of China
  • C. Feng, K.Q. Zhang, Z.T. Zhao
    SSRF, Shanghai, People’s Republic of China
  • D. Gu
    SARI-CAS, Pudong, Shanghai, People’s Republic of China
 
  X-ray free-electron lasers (FEL) have contributed to many frontier applications of nanoscale science which benefit from its extraordinary properties. During FEL commissioning, the beam status optimization especially orbit correction is particularly significant for FEL amplification. For example, the deviation between beam orbit and the magnetic center of undulator can affect the interaction between the electron beam and the FEL pulse. Usually, FEL commissioning requires a lot of effort for multi-dimensional parameters optimization in a time-varying system. Therefore, advanced algorithms are needed to facilitate the commissioning procedure. In this paper, we propose an online method to optimize the FEL power and transverse coherence by using a twin delayed deep deterministic policy gradient (TD3) algorithm. The algorithm exhibits more stable learning convergence and improves learning performance because the overestimation bias of policy gradient methods is suppressed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT013  
About • Received ※ 17 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT016 Status of the THz@PITZ Project - The Proof-of-Principle Experiment on a THz SASE FEL at the PITZ Facility undulator, FEL, dipole, experiment 1033
 
  • T. Weilbach, P. Boonpornprasert, G.Z. Georgiev, G. Koss, M. Krasilnikov, X.-K. Li, A. Lueangaramwong, F. Mueller, A. Oppelt, S. Philipp, F. Stephan
    DESY Zeuthen, Zeuthen, Germany
 
  Funding: This work was supported by the European XFEL research and development program.
In order to allow THz pump/X-ray probe experiments at full bunch repetition rate for users at the European XFEL, the Photo Injector Test Facility at DESYin Zeuthen (PITZ) is building a prototype of an accelerator-based THz source. The goal is to generate THz SASE FEL radiation with a mJ energy level per bunch using an undulator driven by the electron beam from PITZ. Therefore, the existing PITZ beam line is extended into a tunnel annex downstream of the existing accelerator tunnel. The final design of the beam line extension consists of a bunch compressor, a collimation system and a beam dump in the PITZ tunnel. In the tunnel annex one LCLS-I undulator is installed for the production of the THz radiation with a quadrupole triplet in front of it for matching the beam parameters for the FEL process. Behind the undulator two screen stations couple out the THz radiation, for measurements of bunch compression, pulse energy or spatial distribution. A dipole separates the electron from the THz beam and a quadrupole doublet transports the electron beam to the beam dump. The installation progress will be presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT016  
About • Received ※ 07 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 25 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT018 Fermi 2.0 Future Upgrade Strategy FEL, simulation, laser, bunching 1041
 
  • L. Giannessi, E. Allaria, L. Badano, F. Bencivenga, C. Callegari, F. Capotondi, D. Castronovo, P. Cinquegrana, M. Coreno, M.B. Danailov, G. De Ninno, P. Delgiusto, A.A. Demidovich, S. Di Mitri, B. Diviacco, W.M. Fawley, M. Ferianis, G. Gaio, F. Gelmetti, G. Kurdi, M. Lonza, M. Malvestuto, M. Manfredda, C. Masciovecchio, I. Nikolov, G. Penco, K.C. Prince, E. Principi, P. Rebernik Ribič, C. Scafuri, N. Shafqat, P. Sigalotti, A. Simoncig, F. Sottocorona, S. Spampinati, C. Spezzani, L. Sturari, M. Trovò, M. Veronese, R. Visintini, M. Zangrando
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • M. Coreno
    CNR-ISM, Trieste, Italy
  • G. Penn
    LBNL, Berkeley, California, USA
  • G. Perosa
    Università degli Studi di Trieste, Trieste, Italy
  • T. Tanaka
    RIKEN SPring-8 Center, Hyogo, Japan
 
  FERMI is studying a series of developments to keep the facility in a world-leading position on the base of the requests coming from the user community, the Scientific Advisory Council and the Machine Advisory Committee. The ultimate goal of the development plan consists in doubling the photon energy range and reducing the pulse duration below the characteristic lifetime of the atomic core levels located in the energy range of the source. One of the most promising approaches is the echo-enabled harmonic generation (EEHG) scheme, relying on two external lasers to precisely control the spectro-temporal properties of the FEL pulse. The implementation of EEHG in the double-stage harmonic cascade presently in use on FEL-2, would allow harmonics as high as 120 enabling to generate coherent pulses down to 2 nm starting from UV lasers. An upgrade of FERMI aimed at reaching the oxygen K-edge requires a profound modification of the FEL configurations and of the main components of the machine, including the linac and the undulator lines. The main aspects of the upgrade strategy will be discussed in this presentation.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT018  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 07 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT019 FERMI FEL-1 Upgrade to EEHG FEL, laser, free-electron-laser, simulation 1044
 
  • C. Spezzani, E. Allaria, L. Badano, D. Castronovo, P. Cinquegrana, M.B. Danailov, R. De Monte, G. De Ninno, P. Delgiusto, A.A. Demidovich, S. Di Mitri, B. Diviacco, M. Ferianis, G. Gaio, F. Gelmetti, L. Giannessi, G. Kurdi, M. Lonza, C. Masciovecchio, I. Nikolov, G. Penco, P. Rebernik Ribič, C. Scafuri, N. Shafqat, P. Sigalotti, F. Sottocorona, S. Spampinati, L. Sturari, M. Trovò, M. Veronese, R. Visintini
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • G. Perosa
    Università degli Studi di Trieste, Trieste, Italy
 
  The Fermi free-electron laser (FEL) facility is operating since 2010 providing the user community with ultrashort pulses in the VUV- XUV range. Using the High Gain Harmonic Generation (HGHG) setup, nearly transform-limited pulses with gigawatt peak power are made available. Furthermore, several multicolor and coherent control schemes are possible and highly required from the user community. To meet the request of extending the spectral range over the whole water window, an upgrade strategy of the FERMI facility has recently initiated. During the first phase of the upgrade, the single cascade FEL-1 will be adapted to operate either in Echo Enabled Harmonic Generation (EEHG) or in HGHG. Required modifications can be achieved with limited impact on FERMI operations and will improve FEL-1’s spectral range, spectral quality and flexibility. The second phase includes modification of the FEL-2 setup and will benefit from the experience gained with phase 1. The two phases will proceed in parallel to the linac upgrade aiming at extending the beam energy to 1.8 GeV. We report here details on the upgrade of the FEL-1 foreseen to provide light to users in the new configuration by spring 2023.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT019  
About • Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 21 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT023 Undulator Tapering Studies of an Echo-Enabled Harmonic Generation Based Free-Electron Laser undulator, FEL, laser, radiation 1047
 
  • F. Pannek, W. Hillert
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
  • S. Ackermann, E. Ferrari, L. Schaper
    DESY, Hamburg, Germany
 
  The free-electron laser (FEL) user facility FLASH at DESY is currently undergoing an upgrade which involves the transformation of one of its beamlines to allow for external seeding via so-called Echo-Enabled Harmonic Generation (EEHG). With this seeding technique it will be possible to provide stable, longitudinal coherent and intense radiation in the XUV and soft X-ray regime at high repetition rate. To ensure an efficient FEL amplification process, sustainable energy exchange between the electrons and the electromagnetic field in the undulator is mandatory. Adequate adjustment of the undulator strength along the beamline allows to compensate for electron energy loss and to preserve the resonance condition. The impact of this undulator tapering on the temporal and spectral characteristics on the EEHG FEL radiation at 4 nm is investigated by means of numerical simulations performed with the FEL code GENESIS 1.3, version 4. Different tapering methods are examined and it is shown that specific tapering of the undulator strength allows to exceed the FEL saturation power while maintaining a clear temporal and spectral shape of the FEL pulse.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT023  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT025 Concept of Electron Beam Diagnostics for PolFEL radiation, FEL, diagnostics, gun 1055
 
  • A.I. Wawrzyniak, G.W. Kowalski, A.M. Marendziak, R. Panaś
    NSRC SOLARIS, Kraków, Poland
  • A. Curcio
    CLPU, Villamayor, Spain
  • P.J. Czuma, M. Krakówiak, P. Krawczyk, R. Kwiatkowski, S. Mianowski, R. Nietubyc, M. Staszczak, J. Szewiński, M. Terka, M. Wójtowicz
    NCBJ, Świerk/Otwock, Poland
  • K. Łasocha
    Jagiellonian University, Kraków, Poland
 
  PolFEL - Polish Free Electron Laser will be driven by a continuous wave superconducting accelerator consist-ing of low emittance superconducting RF electron gun, four accelerating cryomodules, bunch compressors, beam optics components and diagnostic elements. The acceler-ator will split in three branches leading to undulators pro-ducing VUV, IR and THz radiation, respectively. Two accelerating cryomodules will be installed before a dogleg directing electron bunches towards IR and THz branches. Additional two cryomodules will be placed in the VUV branch accelerating electron bunches up to 185 MeV at 50 kHz repetition rate. Moreover, the electron beam after passing the VUV undulator will be directed to the Inverse Compton Scattering process for high energy photons experiments in a dedicated station. In order to measure and optimise the electron beam parameters along the entire accelerator the main diagnostics components like BPMs, charge monitors, YAG screens, coherent diffrac-tion radiation (CDR) monitors and beam loss monitors are foreseen. Within this presentation the concept of the electron beam diagnostics will be discussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT025  
About • Received ※ 09 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT027 Numerical Simulation of a Superradiant THz Source at the PITZ Facility radiation, FEL, undulator, simulation 1063
 
  • N. Chaisueb, S. Rimjaem
    Chiang Mai University, Chiang Mai, Thailand
  • P. Boonpornprasert, M. Krasilnikov, X.-K. Li, A. Lueangaramwong
    DESY Zeuthen, Zeuthen, Germany
  • S. Rimjaem
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  An accelerator-based THz source is under development at the Photo Injector Test Facility at DESY in Zeuthen (PITZ). The facility can produce high brightness electron beams with high charge and small emittance. Currently, a study on development of a tunable high-power THz SASE FEL for supporting THz-pump, X-ray-probe experiments at the European XFEL is underway. An LCLS-I undulator, a magnetic chicane bunch compressor, and THz pulse diagnostics have been installed downstream the previously existing setup of the PITZ beamline. Additional to the SASE FEL, a possibility to generate superradiant THz undulator radiation from short electron bunches is under investigation, which is the focus in this study. Numerical simulations of the superradiant THz radiation by using sub-picosecond electron bunches with energy of 6 - 22 MeV and bunch charge up to 2 nC produced from the PITZ accelerator are performed. The results show that the radiation with a spectral range of 0.5 to 9 THz and a pulse energy in the order of sub-uJ can be obtained. The results from this study can be used as a benchmark for the future development.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT027  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 07 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT028 THz Undulator Radiation Based on Super-Radiant Technique at Chiang Mai University undulator, radiation, software, simulation 1067
 
  • E. Kongmon
    IST, Chiang Mai, Thailand
  • N. Chaisueb, S. Rimjaem
    Chiang Mai University, Chiang Mai, Thailand
  • S. Rimjaem
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  A linear accelerator system at the PBP-CMU Electron Linac Laboratory is used as an electron source for generating coherent THz radiation and MIR-FEL. To achieve high power THz radiation, the super-radiant technique using pre-bunched electrons and undulator magnet is utilized. In this study, we investigate the generation of such radiation with comparable properties as the FEL. The beamline composes of a 180-degree magnetic bunch compressor, a 2 m-electromagnet undulator, quadrupole magnets and diagnostic devices. This work includes the undulator design and investigation on properties of electron beam and THz radiation. Based-on the results of beam dynamic study, the optimized electron beams have an energy in a range of 10-16 MeV, a bunch charge of 100 pC, and a bunch length of 300 fs. The radiation with frequency covering from 0.5 to 3 THz yields a peak power of 5.21 MW at 1.15 THz. This information was used as an initial parameter for undulator design by using the CST-EM Studio software. It has 19.5 periods with a period length of 100 mm. The design results show that the maximum magnetic field is 0.2317 T. The results of this study are used as the guideline for construction of the undulator and the THz-FEL beamline.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT028  
About • Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT029 Infrared Free-Electron Laser Project in Thailand FEL, radiation, experiment, FEM 1070
 
  • S. Rimjaem, N. Chaisueb, P. Kitisri, K. Kongmali, E. Kongmon, P. Nanthanasit, S. Pakluea, J. Saisut, S. Sukara, K. Techakaew, C. Thongbai
    Chiang Mai University, Chiang Mai, Thailand
  • P. Apiwattanakul, P. Jaikaew, W. Jaikla, N. Kangrang
    Chiang Mai University, PBP Research Facility, Chiang Mai, Thailand
  • M. Jitvisate
    Suranaree University of Technology, Nakhon Ratchasima, Thailand
  • M.W. Rhodes
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  The infrared free-electron laser (IR FEL) project is established at Chiang Mai University in Thailand with the aim to provide experimental stations for users utilizing accelerator-based terahertz (THz) and mid-infrared (MIR) radiation. Main components of the system include a thermionic RF gun, an alpha magnet as a bunch compressor and energy filter, a standing-wave RF linac, a THz transition radiation (THz-TR) station, two magnetic bunch compressors and beamlines for MIR/THz FEL. The system commissioning is ongoing to produce the beams with proper properties. Simulation results suggest that the oscillator MIR-FEL with wavelengths of 9.5-16.6 um and pulse energies of 0.15-0.4 uJ can be produced from 60-pC electron bunches with energy of 20-25 MeV. The super-radiant THz-FEL with frequencies of 1-3 THz and 700 kW peak power can be produced from 10-16 MeV electron bunches with a charge of 50 pC and a length of 200-300 fs. Furthermore, the THz-TR with a spectral range of 0.3-2.5 THz and a pulse power of up to 1.5 MW can be obtained. The MIR/THz FEL will be used as high-brightness light source for pump-probe experiments, while the coherent THz-TR will be used in time-domain spectroscopy.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT029  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT030 Design and Simulation of the MIR-FEL Generation System at Chiang Mai University FEL, cavity, undulator, simulation 1074
 
  • S. Sukara, K. Kongmali, S. Rimjaem
    Chiang Mai University, Chiang Mai, Thailand
  • H. Ohgaki
    Kyoto University, Kyoto, Japan
 
  At the PBP-CMU Electron Linac Laboratory, the system to generate MIR-FEL using the electron linac has been developed. In this contribution, the design and simulation results of the MIR-FEL generation system are presented. The system is designed as the oscillator-FEL type consisting of two mirrors and a 1.6-m permanent planar undulator. The middle of the undulator is determined as the laser beam waist position. Both two mirrors are the concave gold-coated copper mirrors placing upstream and downstream the optical cavity, which has a total length of 5.41 m. The FEL is designed to coupling out at a hole with diameter of 2 mm on the upstream mirror. The optical cavity is optimized to obtain high FEL gain and high FEL power using GENESIS 1.3 simulation code. The electron beam with energy of 25 MeV is used in the consideration. As a result, the MIR-FEL with central wavelength of 13.01 ’m is obtained. The optimum upstream and downstream mirror curvatures are 3.091 m and 2.612 m, respectively, which give the Rayleigh length of 0.631 m. This optical cavity yields the power coupling ratio of 1:1000 and the FEL gain of up to 40%. The extracted MIR-FEL peak power in 100 kW scale is obtained at the coupling hole. The construction of the practical MIR-FEL system is conducted based on the results from this study.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT030  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT032 Simulating Beam Transport with Permanent Magnet Chicane for THz Fel FEL, undulator, GUI, laser 1077
 
  • A.C. Fisher, M.P. Lenz, P. Musumeci, A. Ody, Y. Park
    UCLA, Los Angeles, USA
  • R.B. Agustsson, T.J. Hodgetts, A.Y. Murokh
    RadiaBeam, Santa Monica, California, USA
 
  Funding: This work was supported by NSF grant PHY-1734215 and DOE grant No. DE-SC0009914 and DE-SC0021190. The undulator construction has been carried out under SBIR/STTR DE-SC0017102 and DE-SC0018559.
Free electron lasers are an attractive option for high average and peak power radiation in the THz gap, a region of the electromagnetic spectrum where radiation sources are scarce, as the required beam and undulator parameters are readily achievable with current technology. However, slippage effects require the FEL to be driven with relatively long and low current electron bunches, limiting amplification gain and output power. Previous work demonstrated that a waveguide could be used to match the radiation and e-beam velocities in a meter-long strongly-tapered helical undulator, resulting in 10\% energy extraction from an ultrashort 200 pC, 5.5 MeV electron beam. We present simulations for a follow-up experiment targeting higher frequencies with improvements to the e-beam transport including a permanent magnet chicane for strong beam compression. FEL simulations show >20\% extraction efficiency from a 125 pC, 7.4 MeV electron beam at 0.32 THz.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT032  
About • Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT034 Modelling of X-Ray Volume Excitation of the XLO Gain Medium Using Flash laser, plasma, simulation, target 1081
 
  • P. Manwani, N. Majernik, B. Naranjo, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • E.C. Galtier, A. Halavanau, C. Pellegrini
    SLAC, Menlo Park, California, USA
 
  Funding: This work was performed with the support of the US Department of Energy under Contract No. DE-AC02-76SF00515 and DESC0009914.
Plasma dynamics and crater formation of laser excited volumes in solids is a complex process due to thermalization, shockwave formation, varying absorption mechanisms, and a wide range of relevant physics timescales. The properties and interaction of such laser-matter systems can be modeled using an equation of state and opacity based multi-temperature treatment of plasma using a radiation hydrodynamics code. Here, we use FLASH, an adaptive mesh radiation-hydrodynamics code, to simulate the plasma expansion following after the initial energy deposition and thermalization of the column, to benchmark the results of experiments undertaken at UCLA on optical laser ablation. These computational results help develop a quantitative understanding of the material excitation process and enable the optimization of the gain medium delivery system for the x-ray laser oscillator project *.
* Halavanau, Aliaksei, et al. "Population Inversion X-Ray Laser Oscillator." Proceedings of the National Academy of Sciences, vol. 117, no. 27, 2020, pp. 15511-15516.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT034  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT035 Introduction of Westwood Linear Accelerator Test Facility in University of California Los Angeles gun, laser, FEL, klystron 1085
 
  • Y. Sakai, G. Andonian, O. Camacho, A. Fukasawa, G.E. Lawler, N. Majernik, P. Manwani, B. Naranjo, J.B. Rosenzweig, O. Williams
    UCLA, Los Angeles, California, USA
 
  Funding: U.S. DOE: DE-SC0009914 U.S. DOD: DARPA GRIT Contract 20204571 U.S. DOE: DE-SC0020409 - Cryo RF
An electron linear accelerator test facility located on UCLA’s southwest campus in Westwood, SAMURAI, is presently being constructed. A RF-based accelerator consists of a compact, 3 MeV S-band hybrid gun capable of velocity bunching to bunch lengths in the 100s fs range with 100s pC of charge. This beam is accelerated by an 1.5 m S-band linac with a peak output energy of 30 MeV which can be directed to either a secondary beamline or remain on the main beamline for final acceleration by a SLAC 3 m S-band linac to an energy of 80 MeV. Further acceleration by advanced boosters such as a cryo-cooled C-band structure or numerous optical or wakefield methods is under active investigation. In combination with a 3 TW Ti:Sapphire laser, initial proof of principle experiments will be conducted on topics including the ultra-compact x-ray free-electron laser, advanced dielectric wakefield acceleration, bi-harmonic nonlinear inverse Compton scattering, and various radiation detectors. Furthermore, development of a tertiary beamline based on an ultra low emittance, cryo-cooled gun will eventually enable two-beam experiments, expanding the facility’s unique experimental capabilities.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT035  
About • Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 20 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT036 Two and Multiple Bunches with the LCLS Copper Linac laser, timing, controls, undulator 1089
 
  • F.-J. Decker, W.S. Colocho, A. Halavanau, A.A. Lutman, J.P. MacArthur, G. Marcus, R.A. Margraf, J.C. Sheppard, J.J. Turner, S. Vetter
    SLAC, Menlo Park, California, USA
 
  Two, four, and even eight bunches were accelerated through the copper linac. Two and four bunches were delivered successfully to photon experiments in both the hard (HXR) and soft (SXR) LCLS x-ray lines. In this paper we will concentrate on the more challenging issues, such as: the BPM deconvolution for both bunches, RF kicks at longer separations, tuning challenges, bridging the communications gap between the photon and electron side, the lower bunch charges for the eight bunch case, and rapid timing scans over several ns. We will describe some of the developed solutions and plans for the rest.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT036  
About • Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT038 FAST-GREENS: A High Efficiency Free Electron Laser Driven by Superconducting RF Accelerator undulator, laser, experiment, radiation 1094
 
  • P. Musumeci, P.E. Denham, A.C. Fisher, Y. Park
    UCLA, Los Angeles, California, USA
  • R.B. Agustsson, T.J. Hodgetts, A.Y. Murokh, M. Ruelas
    RadiaBeam, Santa Monica, California, USA
  • L. Amoudry
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • D.R. Broemmelsiek, S. Nagaitsev, J. Ruan, J.K. Santucci, G. Stancari, A. Valishev
    Fermilab, Batavia, Illinois, USA
  • D.L. Bruhwiler, J.P. Edelen, C.C. Hall
    RadiaSoft LLC, Boulder, Colorado, USA
  • A.H. Lumpkin, A. Zholents
    ANL, Lemont, Illinois, USA
 
  Funding: This work is supported by DOE grants DE-SC0017102, DE-SC0018559 and DE-SC0009914
In this paper we’ll describe the FAST-GREENS experimental program where a 4 m-long strongly tapered helical undulator with a seeded prebuncher is used in the high gain TESSA regime to convert a significant fraction (up to 10 %) of energy from the 240 MeV electron beam from the FAST linac to coherent 515 nm radiation. We’ll also discuss the longer term plans for the setup where by embedding the undulator in an optical cavity matched with the high repetition rate from the superconducting accelerator (3,9 MHz), a very high average power laser source can be obtained. Eventually, the laser pulses can be redirected onto the relativistic electrons to generate by inverse compton scattering a very high flux of circularly polarized gamma rays for polarized positron production.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT038  
About • Received ※ 09 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 02 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT044 High-Power Attosecond Pulses via Cascaded Amplification FEM, laser, experiment, ISOL 1101
 
  • P.L. Franz, Z.H. Guo, S. Li, R. Robles
    Stanford University, Stanford, California, USA
  • D.K. Bohler, D.B. Cesar, X. Cheng, J.P. Cryan, T.D.C. Driver, J.P. Duris, A. Kamalov, S. Li, A. Marinelli, R. Obaid, R. Robles, N.S. Sudar, A.L. Wang, Z. Zhang
    SLAC, Menlo Park, California, USA
 
  Funding: This work was supported by US Department of Energy Contracts No. DE-AC02-76SF00.
The timescale for electron motion in molecular systems is on the order of hundreds of attoseconds, and thus the time-resolved study of electronic dynamics requires a source of sub-femtosecond x-ray pulses. Here we report the experimental generation of sub-femtosecond duration soft x-ray free electron laser (XFEL) pulses with hundreds of microjoules of energy using fresh-slice amplification in two cascaded stages at the Linac Coherent Light Source. In the first stage, an enhanced self-amplified spontaneous emission (ESASE) pulse is generated using laser-shaping of the electron beam at the photocathode*. The electron bunch is then delayed relative to the pulse by a magnetic chicane, allowing the radiation to slip onto a fresh slice of the bunch, which amplifies the ESASE pulse in the second cascade stage. Angular streaking** characterizes the experimental pulse durations as sub-femtosecond at ~465 eV in the experiment.
* Zhang, Z. et al. New J. Phys. 22 (2020)
** Li, S. et al. Optics Express 26.4 (2018): 4531-4547.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT044  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT048 bERLinPro Becomes SEALab: Status and Perspective of the Energy Recovery Linac at HZB linac, SRF, cavity, experiment 1110
 
  • A. Neumann, B. Alberdi-Esuain, T. Birke, P. Echevarria, D. Eichel, F. Falkenstern, R. Fleischhauer, A. Frahm, F. Göbel, A. Heugel, F. Hoffmann, H. Huck, T. Kamps, S. Klauke, G. Klemz, J. Kolbe, J. Kühn, B.C. Kuske, J. Kuszynski, S. Mistry, N. Ohm, H. Ploetz, S. Rotterdam, O. Schappeit, G. Schindhelm, C. Schröder, M. Schuster, H. Stein, E. Suljoti, Y. Tamashevich, M. Tannert, J. Ullrich, A. Ushakov, J. Völker, C. Wang
    HZB, Berlin, Germany
  • T. Kamps
    HU Berlin, Berlin, Germany
 
  Funding: Work supported by German Bundesministerium für Bildung und Forschung, Land Berlin, and grants of Helmholtz Association
Since end of the year 2020 the energy recovery linac (ERL) project bERLinPro of Helmholtz-Zentrum Berlin has been officially completed. But what is the status of this facility, the next scientific goals in the framework of accelerator physics at HZB, what are the perspectives? To reflect the continuation of this endeavor and the broadening of applications of this machine from high current SRF based energy recovery concept up to an ultrafast electron diffraction (UED) facility producing shortest electron pulses, the facility is now named Sealab, Superconducting RF Electron Accelerator Laboratory. In this contribution, an overview of lessons learned so far, the status of the machine, the coming set up and commissioning steps with an outlook to midterm and future applications will be given. In summary, Sealab will expand, including the ERL application, and become a general accelerator physics and technology test machine to employ UED as a first study case and will also be an ideal testbed to investigate new control schemes based on digital twins or machine learning methods.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT048  
About • Received ※ 06 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT050 Investigation of Polarization Dependent Thomson Scattering in an Energy-Recovering Linear Accelerator on the Example of Mesa scattering, photon, HOM, polarization 1114
 
  • C.L. Lorey, A. Meseck
    KPH, Mainz, Germany
 
  Funding: GRK 2128 AccelencE funded by the DFG
At the Johannes Gutenberg University (JGU) in Mainz, a new accelerator is currently under construction in order to deliver electron beams of up to 155 MeV to two experiments. The Mainz Energy-recovering Superconducting Accelerator (MESA) will offer two modes of operation, one of which is an energy-recovering (ER) mode. As an ERL, MESA, with it’s high brightness electron beam, is a promising accelerator for supplying a Thomson back scattering based Gamma source. Furthermore, at MESA, the polarization of the electron beam can be set by the injector. The aim of this work is to provide a concept and comprehensive analysis of the merit and practical feasibility of a Thomson backscattering source at MESA under consideration of beam polarization and transversal effects. In this paper, an overview and results of our semi analytical approach to calculate various Thomson back scattering light source scenarios at MESA will be given. Furthermore we will discuss the benefits of using polarized electrons in combination with a polarized laser beam.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT050  
About • Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT051 Reconstruction and Beam-Transport Study of the cERL Dump Line for High-Power IR-FEL Operation FEL, cavity, operation, beam-transport 1117
 
  • N. Nakamura, K. Harada, N. Higashi, R. Kato, S. Nagahashi, K.N. Nigorikawa, T. Nogami, T. Obina, H. Sagehashi, H. Sakai, M. Shimada, R. Takai, O.A. Tanaka, Y. Tanimoto, T. Uchiyama, A. Ueda
    KEK, Ibaraki, Japan
 
  Funding: This work is supported by a NEDO project "Development of advanced laser processing with intelligence based on high-brightness and high-efficiency laser technologies."
A significant FEL pulse energy was successfully generated at the cERL IR-FEL in Burst mode where a macro pulse of about 1 microsecond or less is repeated at the maximum frequency of 5 Hz. In the next step, high-power FEL operation in CW mode should be carried out with energy recovery by increasing electron bunches drastically. However, momentum spread of the electron beam increases due to the FEL-light emission and the space charge effects and may cause serious beam loss by exceeding the momentum acceptance of the cERL downstream of the FEL. Therefore, we reconstructed the dump line in Autumn 2020 in order to greatly increase the momentum acceptance with improvement of the beam-tuning flexibility. Then we performed the beam-transport study of the reconstructed dump line in March 2021 by injecting the beam directly from the injector without passing the recirculation loop. In this paper, we present the reconstructed dump line and the beam-transport study.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT051  
About • Received ※ 16 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 13 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT052 Proposal for Non-Destructive Electron Beam Diagnostic with Laser-Compton Backscattering at the S-Dalinac photon, laser, scattering, linac 1121
 
  • M.G. Meier, M. Arnold, J. Enders, N. Pietralla
    TU Darmstadt, Darmstadt, Germany
 
  Funding: Work supported in part by the state of Hesse within the research cluster ELEMENTS (project ID 500/10.006) and the LOEWE research cluster Nuclear Photonics and by DFG through GRK 2128 "Accelence" and Inst163/308-1 FUGG.
To recover a large fraction of energy from the accelerator process in an energy-recovery linac, experiments, secondary-beam production, and beam diagnostics must be non-destructive and/or, hence, feature a low interaction probability with the very intense electron-beam. Laser-Compton backscattering can provide a quasi-monochromatic highly polarized X-ray to γ-ray beam without strongly affecting the electron beam due to the small recoil and the small Compton cross-section. Highest energies of the scattered photons are obtained for photon-scattering angles of \ang{180}, i. e., backscattering. A project at TU Darmstadt foresees to synchronize a highly repetitive high-power laser with the Superconducting DArmstadt electron LINear ACcelerator S\hbox{-}DALINAC, capable of running in energy recovery mode * to realize a laser-Compton backscattering source with photon beam energy up to §I{180}{\kilo\electronvolt}. The source will be first used as a diagnostic tool for determining and monitoring key electron-parameters, in particular energy and the energy spread at the S\hbox{-}DALINAC operation. Results are foreseen to be used for optimizing the design of laser-Compton backscattering sources at energy-recovery linacs.
*M. Arnold et al., Phys. Rev. Accel. Beams 23, 020101(2020)
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT052  
About • Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT053 Study of Bunch Length Measurement by Forward Coherent Smith-Purcell Radiation radiation, experiment, background, detector 1125
 
  • H. Yamada, H. Hama, F. Hinode, K. Kanomata, S. Kashiwagi, S. Miura, T. Muto, I. Nagasawa, K. Nanbu, H. Saito, K. Shibata, K. Takahashi
    Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
 
  We are currently conducting basic research on the development of a non-destructive real-time bunch length monitor using coherent Smith-Purcell radiation at the t-ACTS test accelerator at the Center for Electron Photon Science, Tohoku University. The angular distribution of coherent Smith-Purcell radiation reflects the longitudinal shape of the electron bunch. Using this, we came up with a method to measure the bunch length from the peak angle of the angular distribution. In this presentation, we mainly report the results of an experiment to determine the bunch length from the peak angle of the angular distribution of coherent Smith-Purcell radiation using a 100 fs electron beam of t-ACTS.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT053  
About • Received ※ 14 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 09 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT054 Generation of Coherent THz Transition Radiation for Time Domain Spectroscopy at the PBP-CMU Electron Linac Laboratory radiation, linac, FEM, experiment 1129
 
  • S. Pakluea
    Chiang Mai University, PBP Research Facility, Chiang Mai, Thailand
  • M. Jitvisate
    Suranaree University of Technology, Nakhon Ratchasima, Thailand
  • S. Rimjaem, J. Saisut, C. Thongbai
    Chiang Mai University, Chiang Mai, Thailand
  • S. Rimjaem, J. Saisut, C. Thongbai
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  The accelerator system at the PBP-CMU Electron Linac Laboratory is used to generate terahertz transition radiation (THz-TR). Due to broad spectrum, it can be used as the light source for THz time-domain spectroscopy (TDS) to measure both the intensity and phase of the THz signal. This contribution presents the generation of the THz-TR produced from 10-20 MeV electron beams and the system preparation for THz TDS. The electron bunches, which are compressed to have a length of femtosecond scale at the experimental station, is used to generate the THz-TR using a 45°-tilted aluminum foil as a radiator. The radiation properties including angular distribution, polarization and radiation spectrum are measured in the accelerator hall and at the TDS station. The radiation spectral range covers up to 2.3 THz with the peak power of 0.5 - 1.25 MW is expected. The effects of electron bunch distribution, divergence of the beam and influence of optical components on the radiation properties were studied. The results show that the considered effects have a significant impact on the TR properties. The Information will be used in the TR characterization that is needed to be interpreted carefully.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT054  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT058 A Machine Learning Approach to Electron Orbit Control at the 1.5 GeV Synchrotron Light Source DELTA storage-ring, network, synchrotron, controls 1137
 
  • D. Schirmer
    DELTA, Dortmund, Germany
 
  Machine learning (ML) methods have found their application in a wide range of particle accelerator control tasks. Among other possible use cases, neural networks (NNs) can also be utilized for automated beam position control (orbit correction). ML studies on this topic, which were initially based on simulations, were successfully transferred to real accelerator operation at the 1.5-GeV electron storage ring of the DELTA accelerator facility. For this purpose, classical fully connected multi-layer feed-forward NNs were trained by supervised learning on measured orbit data to apply local and global beam position corrections. The supervised NN training was carried out with various conjugate gradient backpropagation learning algorithms. Afterwards, the ML-based orbit correction performance was compared with a conventional, numerical-based computing method. Here, the ML-based approach showed a competitive orbit correction quality in a fewer number of correction steps.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT058  
About • Received ※ 20 May 2022 — Accepted ※ 16 June 2022 — Issue date ※ 25 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT065 Dispersion-Free Steering Beam Based Alignment at SwissFEL undulator, quadrupole, FEL, alignment 1163
 
  • E. Ferrari, M. Calvi, R. Ganter, C. Kittel, E. Prat, S. Reiche, T. Schietinger
    PSI, Villigen PSI, Switzerland
  • C. Kittel
    University of Malta, Information and Communication Technology, Msida, Malta
 
  Micron-level alignment of the undulator line is required for successful operation of linear accelerator based high gain free electron lasers to produce powerful radiation at X-rays’ wavelengths. Such precision in the straightness of the trajectory allows for an optimal transverse superposition between the electrons and the photon beam. This is extremely challenging and can only be achieved via beam-based techniques. In this paper we will report on the dispersion-free steering approach implemented at SwissFEL, that helped achieving improved performance for both the hard and soft X-ray beamlines.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT065  
About • Received ※ 16 May 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT067 Development of a Trigger Distribution System Based on MicroTCA.4 timing, FPGA, controls, electronics 1171
 
  • H. Maesaka, N. Hosoda, T. Inagaki, E. Iwai, T. Ohshima
    RIKEN SPring-8 Center, Hyogo, Japan
  • N. Hosoda, T. Inagaki, E. Iwai, H. Maesaka, T. Ohshima
    JASRI, Hyogo, Japan
 
  We developed a MicroTCA.4 (MTCA.4) module to generate and distribute trigger timing signals. This module has 16 LVDS inputs and 16 LVDS outputs each on the front panel and the Zone 3 connector, and 8 M-LVDS I/O’s for MTCA.4 backplane. The trigger timing of each output can be precisely adjusted with the interval of 238 MHz or 509 MHz clocks by a 24-bit counter. The timing can also be fine-tuned by ~80 ps tap delay. This module has additional 5 optical transceivers, one for receiving trigger signals from upstream and four for fanouts to downstream. A master module distributes trigger signals, trigger counts, and event data through optical links. Slave modules generate trigger output signals with appropriate delays based on the event data and the local setting for each output channel. The timing jitter was measured to be 40 ps std, which is significantly smaller than the clock period of 238 MHz or 509 MHz. This system can also distribute an alarm signal received by a slave module to take data at a faulty situation. Trigger systems with this module have been utilized in SPring-8, SACLA, and NewSUBARU and stably synchronize various accelerator components with sufficient timing accuracy.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT067  
About • Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT068 Transverse and Longitudinal Modulation of Photoinjection Pulses at FLUTE laser, injection, cathode, controls 1174
 
  • M. Nabinger, A.-S. Müller, M.J. Nasse, C. Sax, J. Schäfer, C. Widmann, C. Xu
    KIT, Eggenstein-Leopoldshafen, Germany
 
  Funding: Supported by the Doctoral School "Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology" (KSETA).
To generate the electrons to be accelerated, a photoinjection laser is used at the linac-based test facility FLUTE (Ferninfrarot Linac- Und Test Experiment) at the Karlsruhe Institute of Technology (KIT). The properties of the laser pulse, such as intensity, laser spot size or temporal profile, are the first parameters to influence the characteristics of the electron bunches. In order to control the initial parameters of the electrons in the most flexible way possible, the laser optics at FLUTE are therefore supplemented by additional setups that allow transverse and longitudinal laser pulse shaping by using so-called Spatial Light Modulators (SLMs). In the future, the control of the SLMs will be integrated into a Machine Learning (ML) supported feedback system for the optimization of the electron bunch properties. In this contribution the first test experiments and results on laser pulse shaping at FLUTE on the way to this project are presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT068  
About • Received ※ 07 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 22 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT070 Surrogate Modelling of the FLUTE Low-Energy Section simulation, network, gun, controls 1182
 
  • C. Xu, E. Bründermann, A.-S. Müller, A. Santamaria Garcia, J. Schäfer
    KIT, Karlsruhe, Germany
 
  Funding: Supported by the Helmholtz Association (Autonomous Accelerator, ZT-I-PF-5-6) and the DFG-funded Doctoral School "Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology".
Numerical beam dynamics simulations are essential tools in the study and design of particle accelerators, but they can be prohibitively slow for online prediction during operation or for systematic evaluations of new parameter settings. Machine learning-based surrogate models of the accelerator provide much faster predictions of the beam properties and can serve as a virtual diagnostic or to augment data for reinforcement learning training. In this paper, we present the first results on training a surrogate model for the low-energy section at the Ferninfrarot Linac- und Test-Experiment (FLUTE).
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT070  
About • Received ※ 30 May 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOTK002 Results of the RF Power Tests of the ESS Cryomodules Tested at CEA cryomodule, cavity, detector, cryogenics 1186
 
  • O. Piquet, S. Berry, A. Bouygues, E. Cenni, G. Devanz, C. Madec, C. Mayri, P. Sahuquet
    CEA-DRF-IRFU, France
  • C. Arcambal, Q. Bertrand, P. Bosland, T. Hamelin
    CEA-IRFU, Gif-sur-Yvette, France
  • M.J. Ellis
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • P. Pierini
    ESS, Lund, Sweden
  • D. Sertore
    INFN/LASA, Segrate (MI), Italy
 
  Eight of the medium and high beta cryomodules deliv-ered to ESS by CEA are tested at CEA before delivery; the two medium and high beta prototypes and the three first of each type of the series. The goal of these tests is to validate the assembly and the performances on few cryomodules before the next cryomodules of the series are delivered to ESS. This paper summarizes the general results obtained during the tests at 2 K and at high RF power, Pmax = 1.1 MW. The cavities reach the ESS re-quirements, Eacc = 16.7 MV/m (Medium beta) and 19.9 MV/m (High beta) with an efficient compensation of the Lorentz detuning by the piezo tuner over the full RF pulse length of 3.6 ms at 14 Hz. After the successful tests at CEA, the first cryomodules have been shipped to ESS where the final acceptance test are performed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK002  
About • Received ※ 03 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOTK004 Time Resolved Field Emission Detection During ESS Cryomodule Tests cavity, cryomodule, radiation, neutron 1192
 
  • E. Cenni, G. Devanz, O. Piquet
    CEA-IRFU, Gif-sur-Yvette, France
  • M. Baudrier, L. Maurice
    CEA-DRF-IRFU, France
 
  At CEA-Saclay we are currently testing the European Spallation Source (ESS) high beta cryomodules (CM). Each cryomodule is equipped with four superconducting elliptical cavities with their ancillaries (fundamental power couplers (FPC), frequency tuners and magnetic shields). The cavity are designed to accelerate protons with relativistic speed about β=0.86 and operate at an accelerating field of 19.9MV/m. During cryomodule test, operational parameters are inspected by powering up one cavity at the time. A dedicated gamma ray detection system has been designed and installed around the cryomodule in order to have a more precise insight into field emission phenomenon occurring during cryomodule operation. Recently we were able to obtain time resolved data concerning radiation emerging from the cavities due to field emission.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK004  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 02 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOTK024 Multipacting Simulation on Half-Wave Resonator for 200 MeV Energy Upgrade of Komac Proton Linac simulation, cavity, multipactoring, linac 1255
 
  • J.J. Dang, H.S. Kim, H.-J. Kwon, S. Lee
    KOMAC, KAERI, Gyeongju, Republic of Korea
 
  Funding: This work was supported through KOMAC operation fund of KAERI by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (KAERI-524320-22).
A superconducting linac is developed at KOrea Multi-purpose Accelerator Complex (KOMAC) for proton beam energy upgrade from 100 MeV to 200 MeV. The SRF linac consists of thirty-six half-wave resonator (HWR) cavities. 350 MHz, β = 0.56 HWR is designed to provide 3.6 MV accelerating voltage. After a fundamental RF design study, an analysis on a multipacting (MP) of HWR is carried out. The MP simulation for the HWR is performed by using CST Particle Studio. To understand a feature of the MP occurrence in the HWR, a particle-in-cell simulation is conducted while changing various conditions such as an RF amplitude, an RF phase, and an emission surface.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK024  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOTK030 X-Rays Energy Measurements During the RFQ Conditioning at the European Spallation Source rfq, detector, ion-source, background 1275
 
  • E. Laface, C.G. Maiano, R. Zeng
    ESS, Lund, Sweden
  • O. Piquet
    CEA-DRF-IRFU, France
 
  The Radio Frequency Quadrupole (RFQ) was conditioned at the European Spallation Source during spring 2021. We used part of the conditioning time to estimate the accelerating potential within the RFQ analyzing the x-rays bremsstrahlung radiation emitted by the electrons released and accelerated in the RFQ. The results of these measurements are in good agreement with the theoretical prediction.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK030  
About • Received ※ 16 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOTK058 Development and Testing of High Power CW 1497 MHz Magnetron cathode, cavity, power-supply, simulation 1351
 
  • M. Popovic, M.A. Cummings, A. Dudas, R.P. Johnson, R.R. Lentz, M.L. Neubauer, T. Wynn
    Muons, Inc, Illinois, USA
  • T. Blassick, J.K. Wessel
    Richardson Electronics Ltd, Lafox, Illinois, USA
  • K. Jordan, R.A. Rimmer, H. Wang
    JLab, Newport News, Virginia, USA
 
  Funding: Work supported by DOE NP STTR grant DE-SC0013203
We have designed, built, and tested a new magnetron tube that generates RF power at 1497 MHz. In the tests so far, the tube has produced CW 9 kW RF power, where the measured power is limited by the test equipment. The final goal is to use it to power superconducting (SC) cavities.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK058  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS011 Progress Towards EEHG Seeding at the DELTA Storage Ring laser, undulator, vacuum, storage-ring 1420
 
  • B. Büsing, A. Held, H. Kaiser, S. Khan, C. Mai, A. Radha Krishnan
    DELTA, Dortmund, Germany
 
  Funding: Funded by BMBF (05K16PEB, 05K19PEB), FZ Jülich, and by the federal state NRW.
Seeding of free-electron lasers (FELs) with external laser pulses triggers the microbunching process such that the spectrotemporal properties of coherently emitted FEL radiation are under better control compared to self-amplified spontaneous emission. High-gain harmonic generation (HGHG) based on the interaction of electrons with a single laser pulse is routinely applied at a few FELs, and echo-enabled harmonic generation (EEHG) with a twofold laser-electron interaction has been demonstrated. Both schemes can be adopted in storage rings for the coherent emission of ultrashort radiation pulses. Coherent harmonic generation (CHG) is the counterpart to HGHG without FEL gain. It has been employed at several storage rings and presently provides ultrashort pulses in the vacuum ultraviolet regime at the 1.5-GeV electron storage ring DELTA operated by the TU Dortmund University. EEHG, which allows to reach higher harmonics of the seed wavelength, has not yet been implemented at any storage ring but is pursued at DELTA as an upgrade plan. The paper presents the layout of the envisaged EEHG facility, and it reviews simulation studies and the technical progress towards EEHG seeding at DELTA.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS011  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS012 Investigation of Spectro-Temporal Properties of CHG Radiation at DELTA laser, radiation, storage-ring, bunching 1423
 
  • A. Radha Krishnan, B. Büsing, A. Held, H. Kaiser, S. Khan, C. Mai, Z. Usfoor, V. Vijayan
    DELTA, Dortmund, Germany
 
  Funding: Funded by DFG (INST 212/236-1 FUGG), BMBF (05K16PEA, 05K19PEB), and by the federal state NRW.
At the synchrotron light source DELTA operated by the TU Dortmund University, the short-pulse facility employs the seeding scheme coherent harmonic generation (CHG) and provides ultrashort pulses in the vacuum ultraviolet and terahertz regime. Here, the interaction of laser pulses with the stored electron bunches results in a modulation of the longitudinal electron density which gives rise to coherent emission at harmonics of the laser wavelength. The spectral and temporal properties of such coherent short pulses can be manipulated by the seed laser properties and chicane strength. CHG spectra at several harmonics of the 800 nm seed laser were recorded using an image-intensified CCD (iCCD) camera and a newly installed XUV spectrometer. Numerical simulations to calculate the spectral phase properties of the seed laser from the observed spectra were carried out.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS012  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 18 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS013 Novel High Repetition Rate CW SRF Linac-Based Multispectral Photon Source FEL, linac, radiation, undulator 1427
 
  • P.E. Evtushenko
    HZDR, Dresden, Germany
 
  We discuss a design of a CW SRF linac-based photon facility for the generation of MIR-THz and VUV pulses at high repetition rates of up to 1 MHz. The MIR-THz sources would cover the frequency range from 0.1 to 30 THz with the pulse energies of a few 100 µJ. The use of the CW SRF linac and the radiation source architecture will allow for high flexibility in the pulse repetition rate. Conventional superradiant THz sources, driven by electron bunches shorter than the radiation wavelength, would cover the wavelength range from 0.1 THz to about 2.5 THz. A different approach is developed to extend the operation of the superradiant undulators well beyond the few THz. For this, a longitudinally modulated electron bunch would be used to achieve significant bunching factors at higher frequencies. The proposed VUV FEL would use the HGHG FEL scheme. It will allow the construction of a unique, fully coherent, high repetition rate source operated with about 30 µJ pulse energy at the first harmonic in the design wavelength range. An FEL oscillator, operating at a wavelength 3-5 times longer than the HGHG system, can generate the seed required for the high repetition rate HGHG scheme.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS013  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS024 Sensitivity of EEHG Simulations to Dynamic Beam Parameters FEL, simulation, radiation, laser 1463
 
  • D. Samoilenko, W. Hillert, F. Pannek
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
  • S. Ackermann, E. Ferrari, N.S. Mirian, P. Niknejadi, G. Paraskaki, L. Schaper
    DESY, Hamburg, Germany
  • F. Curbis, M.A. Pop, S. Werin
    MAX IV Laboratory, Lund University, Lund, Sweden
 
  Currently, the Free electron laser user facility FLASH at DESY is undergoing a significant upgrade involving the complete transformation of one of its beamlines to allow external seeding. With the Echo-Enabled Harmonic Generation (EEHG) seeding method, we aim for the generation of fully coherent XUV and soft X-ray pulses at wavelengths down to 4 nm. The generated FEL radiation is sensitive to various electron beam properties, e.g., its energy profile imprinted either deliberately or by collective effects such as Coherent Synchrotron Radiation (CSR). In dedicated particle tracking simulations, one usually makes certain assumptions concerning the beam properties and the collective effects to simplify implementation and analysis. Here, we estimate the influence of some of the common assumptions made in EEHG simulations on the properties of the output FEL radiation, using the example of FLASH and its proposed seeding beamline. We conclude that the inherent properties of the FLASH1 beam, namely the negatively chirped energy profile, has dominant effect on the spectral intensity profile of the radiators output compare to that of the CSR induced chirp.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS024  
About • Received ※ 20 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 24 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS030 Event Tree Model for Safety Reliability Analysis of High Energy Electron 1.2 GeV Radiation Monitoring System Design radiation, monitoring, synchrotron, EPICS 1479
 
  • P. Aim-O, P. Kulthanasomboon, N.S. Pamungkas, S. Ruengpoonwittaya, M. Sophon, N. Sumano, A. Thongwat
    SLRI, Nakhon-Ratchasima, Thailand
  • K. Manasatitpong
    Synchrotron Light Research Institute (SLRI), Muang District, Thailand
 
  Funding: The Science, Research, and Innovation Fund (SRI fund)
The SPS Radiation Monitoring System (SPSRMS) has been designed to measure the ionizing radiation which are generated from the high-energy electron 1.2 GeV. SPSRMS design shall be performed to assure of the adequate performance system in order to prevent the radiation exposure of workers and general public in the synchrotron facility. The research purpose is to evaluate the frequency of failure of real-time radiation monitoring system design that might be happened from the abnormal case which is unable to transfer the important radiation dose continuously. An Event Tree Analysis (ETA) had been approached to evaluate the safety reliability of the SPSRMS which is a method of deducing possibilities and outcomes in a chronological order. This method has been determined the probability of possible negative outcomes that can cause harm and result from the chosen initiating event. The scenario results showed that reliability was increased from 99.71%±19.57% to 99.80%±19.58% (95% confidential level) after adding redundancy in all the devices. The reliability assessment results of SPSRMS are presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS030  
About • Received ※ 30 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS044 Dielectric Loaded THz Waveguide Experimentally Optimized by Dispersion Measurements GUI, experiment, higher-order-mode, acceleration 1526
 
  • M.J. Kellermeier, R.W. Aßmann, K. Flöttmann, F. Lemery
    DESY, Hamburg, Germany
  • R.W. Aßmann
    LNF-INFN, Frascati, Italy
  • W. Hillert
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
 
  Emerging high power THz sources pave the road for THz- driven acceleration of ultra-short bunches, and enable their manipulation for diagnostic purposes. Due to the small feature sizes of THz-guiding devices new methods are necessary for their electromagnetic characterization. A new technique has recently been developed which characterizes THz waveguides with respect to their dispersion relations and attenuation. Here, the method is applied to circular waveguides, partially filled with polymer capillaries of different thicknesses, to find a suitable size for THz driven streaking at 287 GHz. Further, rough 3d-printed metallic waveguides are measured to study the effect of roughness on attenuation and phase constant. In general, additive manufacturing techniques show promise for advanced integrated designs of THz driven structures.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS044  
About • Received ※ 05 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS053 Start-to-End Simulations of the LCLS-II HE Free Electron Laser FEL, undulator, photon, simulation 1549
 
  • D.B. Cesar, G. Marcus, H.-D. Nuhn, T.O. Raubenheimer
    SLAC, Menlo Park, California, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
 
  Funding: This work is supported in part by DOE Contract No. DE-AC02-76SF00515
In this proceeding we present start-to-end simulations of the LCLS-II-HE free electron laser. The HE project will extend the LCLS-II superconducting radio-frequency (SRF) linac from 4 GeV to 8 GeV in order to produce hard x-rays from the eponymous hard x-ray undulators (26 mm period). At the same time, soft x-ray performance is preserved (and extended into the tender regime) by using longer period undulators (56 mm period) than were originally built for LCLS-II (39 mm period). Here we use high-fidelity numerical particle simulations to study the performance of several SASE beamline configurations, and compare the resulting x-ray energy, power, duration, and transverse properties. Using the LCLS-II normal-conducting gun, we find that the x-ray pulse energy drops off rapidly above ~15 keV, while using the lower emittance beam from a proposed SRF gun, we improve the cutoff to ~20 keV.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS053  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOMS058 C-Band High Gradient Testing of the Benchmark a/λ=0.105 Cavity cavity, GUI, coupling, klystron 1564
 
  • E.I. Simakov, V. Gorelov, T. Tajima, M.R.A. Zuboraj
    LANL, Los Alamos, New Mexico, USA
  • S. Biedron
    Element Aero, Chicago, USA
  • S. Biedron
    UNM-ECE, Albuquerque, USA
  • M.E. Middendorf
    ORNL RAD, Oak Ridge, Tennessee, USA
 
  Funding: Los Alamos National Laboratory LDRD Program
This poster will report the results of high gradient testing of the benchmark C-band RF cavity. Modern applications such as X-ray sources require accelerators with optimized cost of construction and operation, naturally calling for high-gradient acceleration. At LANL we commissioned a test stand (CERF-NM) powered by a 50 MW, 5.712 GHz Canon klystron. The test stand is capable of conditioning accelerating cavities for operation at surface electric fields in excess of 300 MV/m. CERF-NM is the first high gradient C-band test facility in the United States. An important milestone for this test stand is to demonstrate conditioning and high gradient testing of the most basic high gradient RF cavity with a geometry that has been extensively studied at other frequencies, such as X-band. The cavity is the three-cell structure with the highest gradient in the central cell and two coupling cells, and the ratio of the radius of the coupling iris to the wavelength a/\lamda=0.105. This presentation will report achieved gradients, breakdown probabilities, and other characteristics measured during the high power operation of this cavity.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS058  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEIXGD1 EIC Beam Dynamics Challenges hadron, luminosity, polarization, cavity 1576
 
  • D. Xu, E.C. Aschenauer, G. Bassi, J. Beebe-Wang, J.S. Berg, W.F. Bergan, M. Blaskiewicz, J.M. Brennan, S.J. Brooks, K.A. Brown, Z.A. Conway, K.A. Drees, A.V. Fedotov, W. Fischer, C. Folz, D.M. Gassner, X. Gu, R.C. Gupta, Y. Hao, C. Hetzel, D. Holmes, H. Huang, J. Kewisch, Y. Li, C. Liu, H. Lovelace III, G.J. Mahler, D. Marx, F. Méot, M.G. Minty, C. Montag, S.K. Nayak, R.B. Palmer, B. Parker, S. Peggs, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, M.P. Sangroula, S. Seletskiy, K.S. Smith, S. Tepikian, R. Than, P. Thieberger, N. Tsoupas, J.E. Tuozzolo, E. Wang, D. Weiss, F.J. Willeke, H. Witte, Q. Wu, W. Xu, A. Zaltsman
    BNL, Upton, New York, USA
  • S.V. Benson, B.R. Gamage, J.M. Grames, T.J. Michalski, E.A. Nissen, J.P. Preble, R.A. Rimmer, T. Satogata, A. Seryi, M. Wiseman, W. Wittmer
    JLab, Newport News, Virginia, USA
  • A. Blednykh, Y. Luo, B. Podobedov, S. Verdú-Andrés
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
  • Y. Cai, Y.M. Nosochkov, G. Stupakov, M.K. Sullivan
    SLAC, Menlo Park, California, USA
  • E. Gianfelice-Wendt
    Fermilab, Batavia, Illinois, USA
  • G.H. Hoffstaetter, D. Sagan, J.E. Unger
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
 
  The Electron Ion Collider aims to produce luminosities of 1034 cm-2s-1 . The machine will operate over a broad range of collision energies with highly polarized beams. The coexistence of highly radiative electrons and nonradiative ions produce a host of unique effects. Strong hadron cooling will be employed for the final factor of 3 luminosity boost.  
slides icon Slides WEIXGD1 [3.952 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEIXGD1  
About • Received ※ 06 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 14 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOXGD2 Electron Accelerator Lattice Design for LHeC with Permanent Magnets linac, synchrotron, synchrotron-radiation, radiation 1587
 
  • D. Trbojevic, J.S. Berg, S.J. Brooks
    BNL, Upton, New York, USA
  • S.A. Bogacz
    JLab, Newport News, Virginia, USA
  • G.H. Hoffstaetter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  Funding: Work performed under the Contract Number DE-AC02-98CH10886 with the auspices of US Department of Energy
We present a new ’green energy’ approach to the Energy Recovery Linac (ERL) the future Electron Ion Collider at LHeC using single beam line made of very strong focusing combined function permanent magnets and the Fixed Field Alternating Linear Gradient (FFA-LG) principle. We are basing our design on recent very successful commissioning results of the Cornell University and Brookhaven National Laboratory ERL Test Accelerator-CBETA.
 
slides icon Slides WEOXGD2 [19.845 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOXGD2  
About • Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 02 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOXSP1 Proposal for a Compact Neutron Generator Based on a Negative Deuterium Ion Beam neutron, target, ion-source, radiation 1599
 
  • K. Jimbo, T. Shirai
    QST-NIRS, Chiba, Japan
  • K. Leung
    LBNL, Berkeley, California, USA
  • K.A. Van Bibber
    UCB, Berkeley, California, USA
 
  Interest in high intensity generators of neutrons for basic and applied science has been growing, and thus the demand for an economical neutron generator has been growing. A major driver for the development of high intensity neutron generators are studies of neutron disturbance in integrated circuits, for which a compact generator that can be easily accommodated in an ordinary size lab would be highly desirable. We have investigated possible designs for neutron generators based on the D-D fusion reaction, which produce direction dependent mono-energetic neutrons with carry-off energy larger than 2.45 MeV. Specifically, we find a negative deuterium ion beam most attractive for this application, and plan to construct such a system with a negative deuterium ion beam of 200 keV energy and 100 mA current as a prototype of this concept.  
slides icon Slides WEOXSP1 [2.581 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOXSP1  
About • Received ※ 17 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOXSP2 All Optical Chartacterization of a Dual Grating Accelerator Structure laser, controls, acceleration, simulation 1602
 
  • S.A. Crisp, P. Musumeci, A. Ody
    UCLA, Los Angeles, USA
 
  Funding: ACHIP grant from the Gordon and Betty Moore Foundation (GBMF4744) U.S. Department of Energy grant DE-AC02-76SF00515 National Science Foundation Graduate Research Fellowship Program Grant DGE1650604.
We present progress and an experimental plan for multi-MeV relativistic energy gain in a dielectric laser-driven accelerator (DLA). Using a 780 nm, 100 fs pulse-front-tilted laser, we achieve interaction with 6 MeV electrons over a 4 mm long structure with 800 nm period. To compensate for resonant defocusing effects, the laser pulse is imprinted with a phase mask, applied by a Spatial Light Modulator, which uses alternating phase focusing (APF) to achieve stable beam transport. The DLA is mechanically mounted with a variable sized gap (600-1200 nm) in order to maximize transmission while maintaining high gradient within the channel. The combination of high interaction length and use of APF confines and accelerates the electrons by up to 3.5 MeV.
 
slides icon Slides WEOXSP2 [1.603 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOXSP2  
About • Received ※ 08 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 29 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOYGD3 Isochronous Mode of the Experimental Storage Ring (ESR) at GSI experiment, sextupole, detector, dipole 1620
 
  • S.A. Litvinov, R. Hess, B. Lorentz, M. Steck
    GSI, Darmstadt, Germany
 
  The isochronous optics of the ESR is a unique ion-optical setting in which the particles within a finite momentum acceptance circulate at constant frequency. It is used for direct mass measurements of short-lived exotic nuclei by a Time-of-Flight method. Besides the mass spectrometry, the isochronous ESR has been used as an instrument for the search of short lived isomers stored in the ring, which was performed in 2021 for the first time. Introduction to the isochronous mode of the ESR, comparison with a standard operational mode, recent machine experiments will be presented here. Possible improvements of the isochronous optics at the ESR and perspectives of the isochronous mode at CR, FAIR will be outlined.  
slides icon Slides WEOYGD3 [6.871 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOYGD3  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 28 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOYSP1 Experiments with Undulator Radiation, Emitted by a Single Electron synchrotron, radiation, photon, undulator 1628
 
  • I. Lobach
    ANL, Lemont, Illinois, USA
  • S. Nagaitsev, A.L. Romanov, A.V. Shemyakin, G. Stancari
    Fermilab, Batavia, Illinois, USA
 
  Funding: The work is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
We study a single electron, circulating in the Fermilab IOTA storage ring and interacting with an undulator through single and multi-photon emissions. The focus of this research is on single-photon and two-photon undulator emissions. We begin by using one Single Photon Avalanche Diode (SPAD) detector to detect the undulator radiation photons and search for possible deviations from the expected Poissonian photon statistics. Then, we go on to use a two-photon interferometer consisting of two SPAD detectors separated by a beam splitter. This allows to test if there is any correlation in the detected photon pairs. In addition, the photocount arrival times can be used to track the longitudinal motion of a single electron and to compare it with simulations. This allowed us to determine several dynamical parameters of the storage ring such as the rf cavity phase jitter and the dependence of the synchrotron motion period on amplitude.
 
slides icon Slides WEOYSP1 [10.952 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOYSP1  
About • Received ※ 05 June 2022 — Revised ※ 25 June 2022 — Accepted ※ 03 July 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOYSP2 First Electron Beam of the ThomX Project linac, gun, HOM, emittance 1632
 
  • C. Bruni, M. Alkadi, J-N. Cayla, I. Chaikovska, S. Chancé, V. Chaumat, O. Dalifard, N. Delerue, K. Dupraz, M. El Khaldi, N. ElKamchi, E.E. Ergenlik, P. Gauron, A. Gonnin, E. Goutierre, H. Guler, M. Jacquet, V. Kubytskyi, P. Lepercq, F. Letellier-Cohen, J.C. Marrucho, B. Mercier, E. Mistretta, H. Monard, A. Moutardier, M. Omeich, V. Soskov, F. Wicek
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
 
  Funding: The present work is financed by the French National Research Agency (ANR) under the Equipex program ANR-10-EQPX-0051.
The ThomX accelerator beam commissioning phase is now ongoing. The 50 MeV electron accelerator complex consists of a 50 MeV linear accelerator and a pulsed mode ring. It is dedicated to the production of X-rays by Compton backscattering. The performance of the beam at the interaction point is demanding in terms of emittance, charge, energy spread and transverse size. The choice of an undamped ring in pulsed mode also stresses the performance of the beam from the linear accelerator. Thus, commissioning includes a beam based alignment and a simulation/experimental matching procedure to reach the X-ray beam requirements. We will present the first 50 MeV electron beam obtained with ThomX and its characteristics.
on behalf of the ThomX collaboration : ThomX collaboration, https://thomx.ijclab.in2p3. fr/collaboration-thomx/, [Online; accessed 19-May- 2022].
 
slides icon Slides WEOYSP2 [80.558 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOYSP2  
About • Received ※ 08 June 2022 — Revised ※ 21 June 2022 — Accepted ※ 04 July 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOZGD1 Design of an LPA-Based First-Stage Injector for a Synchrotron Light Source plasma, laser, beam-loading, simulation 1639
 
  • X.Y. Shi, H.S. Xu
    IHEP, Beijing, People’s Republic of China
 
  Study of plasma-based acceleration has been a frontier of accelerator community for decades. The beam performance obtained from a laser-plasma based accelerator (LPA) becomes higher and higher. Nowadays, a combination of LPAs and the conventional RF accelerators is a trend. One of the interesting directions to go is to replace a LINAC by an LPA as the first-stage injector of a synchrotron light source. In this paper, we present a physical design of a 500 MeV LPA-based first-stage injector for a synchrotron light source.  
slides icon Slides WEOZGD1 [8.971 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOZGD1  
About • Received ※ 15 June 2022 — Revised ※ 22 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEINGD1 Industry and Accelerator Science, Technology, and Engineering - the Need to Integrate (Building Bridges) laser, radiation, network, MMI 1644
 
  • R. Geometrante
    KYMA, Trieste, Italy
  • S. Biedron
    Element Aero, Chicago, USA
  • E. Braidotti
    CAEN ELS srl, Trieste, Italy
  • J.M.A. Priem
    VDL ETG, Eindhoven, The Netherlands
  • J.C. Rugsancharoenphol
    FTI, Bangkok, Thailand
  • S.L. Sheehy
    The University of Melbourne, Melbourne, Victoria, Australia
  • M. Vretenar
    CERN, Meyrin, Switzerland
 
  Abstract  
slides icon Slides WEINGD1 [36.079 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEINGD1  
About • Received ※ 05 July 2022 — Accepted ※ 04 July 2022 — Issue date ※ 05 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEIZSP2 Trapping of Neutral Molecules by the Electromagnetic Beam Field dipole, vacuum, simulation, alignment 1649
 
  • G. Franchetti
    GSI, Darmstadt, Germany
  • F. Zimmermann
    CERN, Meyrin, Switzerland
 
  Neutral uncharged molecules are affected by the electromagnetic field of a charged particle beam if they carry either an electric or a magnetic dipole moment. The residual gas in an accelerator beam pipe consists of such molecules. In this paper we study their dynamics. Under a few approximations, whose validity we explore and justify, we derive the equations of motion of neutral molecules and their invariants, determine the conditions for these neutral molecules to become trapped in the field of the beams as function of beam-pipe temperature, and compute the resulting enhancement of molecule density in the vicinity of the beam. We demonstrate that large agglomerates of molecules, "flakes," are much more likely to be pulled into the beam than single molecules, and suggest that this phenomenon might help explain some beam observations at the Large Hadron Collider.  
slides icon Slides WEIZSP2 [6.142 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEIZSP2  
About • Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEOZSP1 Longitudinal Bunch Shaping Using an X-Band Transverse Deflecting Cavity Powered by Wakefield Power Extractor at Argonne Wakefield Accelerator Facility wakefield, quadrupole, simulation, acceleration 1655
 
  • S.Y. Kim, G. Chen, D.S. Doran, W. Liu, J.G. Power, E.E. Wisniewski
    ANL, Lemont, Illinois, USA
  • A. Bibian, C.-J. Jing, E.W. Knight, S.V. Kuzikov
    Euclid TechLabs, Solon, Ohio, USA
  • P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
 
  Funding: This project is supported under DoE SBIR Phase I Grant No. DE-SC0021733. This work is also supported by Department of Energy, Office of Science, under contract No. DEAC02-06CH11357.
Longitudinal bunch shaping using transverse deflecting cavities (TDC) was recently proposed*. This configuration is well suited for shaping the current profile of high-charge bunches since it does not use dipole magnets, and therefore, is not prone to deleterious effects arising from coherent synchrotron radiation. An intercepting mask located downstream of the first TDC, which introduce a spatiotemporal correlation, transversely shape the beam. Downstream of the second TDC, upon removal of the cross-plane correlation, the bunch is temporally shaped. In this paper, we investigate longitudinal bunch shaping with an X-band TDC powered by an X-band, short-pulse wakefield Power Extraction and Transfer Structure (PETS), where the wakefield from the drive beam propagating through the PETS is the power source. We describe the RF designs of the X-band TDC and the configuration of the overall shaping system. Finally, we explore via beam-dynamics simulations the performances of the proposed shaper and its possible application to various bunch shapes relevant to beam-driven acceleration and coherent radiation generation.
*Gwanghui Ha et al., Phys. Rev. Accel. Beams 23, 072803, 2020
 
slides icon Slides WEOZSP1 [6.235 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOZSP1  
About • Received ※ 14 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST001 Radiation Load Studies for Superconducting Dipole Magnets in a 10 TeV Muon Collider collider, radiation, shielding, dipole 1671
 
  • D. Calzolari, C. Carli, B. Humann, A. Lechner, G. Lerner, F. Salvat Pujol, D. Schulte, K. Skoufaris
    CERN, Meyrin, Switzerland
  • B. Humann
    TU Vienna, Wien, Austria
 
  Among the various future lepton colliders under study, muon colliders offer the prospect of reaching the highest collision energies. Despite the promising potential of a multi-TeV muon collider, the short lifetime of muons poses a severe technological challenge for the collider design. In particular, the copious production of decay electrons and positrons along the collider ring requires the integration of continuous radiation absorbers inside superconducting magnets. The absorbers are needed to avoid quenches, reduce the heat dissipation in the cold mass and prevent magnet failures due to long-term radiation damage. In this paper, we present FLUKA shower simulations assessing the shielding requirements for high-field magnets of a 10 TeV muon collider. We quantify in particular the role of synchrotron photon emission by decay electrons and positrons, which helps in dispersing the energy carried by the decay products. For comparison, selected results for a 3 TeV muon collider are also presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST001  
About • Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST002 Synchrotron Radiation Impact on the FCC-ee Arcs shielding, radiation, neutron, electronics 1675
 
  • B. Humann
    TU Vienna, Wien, Austria
  • F. Cerutti, B. Humann, R. Kersevan
    CERN, Meyrin, Switzerland
 
  Synchrotron radiation (SR) emitted by electron and positrons beams represents a major loss source in high energy circular colliders, such as the lepton version of the Future Circular Collider (FCC-ee) at CERN. In particular, for the operation mode at 182.5 GeV (above the top pair threshold), its spectrum makes it penetrate well beyond the vacuum chamber walls. In order to optimize its containment, dedicated absorbers are envisaged. In this contribution we report the energy deposition studies performed with FLUKA to assess heat load, time-integrated dose, power density and particle fluence distribution in the machine components and the surrounding environment. Different choices for the absorber material were considered and shielding options for electronics were investigated. Furthermore, possible positions for the booster ring were reviewed from the radiation exposure point of view.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST002  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST009 Muon Collider Based on Gamma Factory, FCC-ee and Plasma Target plasma, positron, emittance, target 1691
 
  • F. Zimmermann, A. Latina
    CERN, Meyrin, Switzerland
  • M. Antonelli, M. Boscolo
    LNF-INFN, Frascati, Italy
  • A.P. Blondel
    DPNC, Genève, Switzerland
  • J.P. Farmer
    MPI-P, München, Germany
 
  Funding: This project has received funding from the European Union’s Horizon 2020 Research and Innovation programme under Grant Agreement No 101004730 (iFAST).
The LEMMA-type muon collider generates muon pairs by the annihilation of 45 GeV positrons with electrons at rest. Due to the small cross section, an extremely high rate of positrons is required, which could be achieved by a ’Gamma factory’ based on the LHC. Other challenges with the LEMMA-type muon production scheme include the emittance preservation of muons and muon-generating positrons upon multiple traversals through a target, and the merging of many separate muon bunchlets. These two challenges may potentially be overcome by (1) operating the FCC-ee booster with a barrier bucket and induction acceleration, so that all positrons of a production cycle are merged into one single superbunch instead of storing ~10,000 separate bunches; and (2) sending the positron superbunch into a plasma target. During the passage of the positron superbunch, the electron density is enhanced 100–1000 fold without any increase in the density of nuclei, so that beamstrahlung and Coulomb scattering are essentially absent. We investigate prospects and difficulties of this approach, including emittance growth due to filamentation in the nonlinear plasma channel and due to positron self-modulation.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST009  
About • Received ※ 08 June 2022 — Revised ※ 23 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST010 Controlling e+/e Circular Collider Bunch Intensity by Laser Compton Scattering laser, collider, scattering, photon 1695
 
  • F. Zimmermann
    CERN, Meyrin, Switzerland
  • T.O. Raubenheimer
    SLAC, Menlo Park, California, USA
 
  Funding: This project receives funding from the European Union’s H2020 Framework Programme under grant agreement no. 951754 (FCCIS).
In the future circular electron-positron collider "FCC-ee", the intensity of colliding bunches must be tightly controlled, with a maximum charge imbalance between collision partner bunches of less than 3-5%. Laser Compton back scattering could be used to adjust and fine-tune the bunch intensity. We discuss a possible implementation and suitable laser parameters.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST010  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST020 EIC Hadron Spin Rotators polarization, proton, storage-ring, hadron 1734
 
  • V. Ptitsyn, J.S. Berg
    BNL, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
The Electron-Ion Collider in BNL will collide polarized electrons with polarized protons or polarized 3He ions. Spin rotators will be used to create the longitudinal beam polarization at a location of the EIC experimental detector. Helical spin rotators utilized for polarized proton operation in present RHIC will be reused in the EIC Hadron Storage Ring. However, due to a significant difference of EIC and RHIC interaction region layouts, the EIC spin rotator arrangement has several challenges. Turning on the EIC spin rotators may lead to a significant spin tune shift. To prevent beam depolarization during the spin rotator turn-on, Siberian Snakes have to be tuned simultaneously with rotators. The EIC spin rotators must be able to operate in a wide energy range for polarized protons and polarized 3He ions. The paper presents the challenges of spin rotator usage in the EIC and remedies assuring the successful operation with the rotators.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST020  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST021 Theoretical Study of Laser Energy Absorption Towards Energetic Proton and Electron Sources laser, target, proton, simulation 1737
 
  • I.M. Vladisavlevici, E. d’Humières
    CELIA, Talence, France
  • D. Vizman
    West University of Timisoara, Timisoara, Romania
 
  Funding: This work was supported by Romanian National Authority for Scientific Research PN 75/2018, Agence Nationale de la Recherche project ANR-17-CE30-0026-Pinnacle, WUT - JINR collaboration project 05-6-1119-2014/2023 (2/2019; 86/2020; 103/2021) and Erasmus+ Student grant (2018/2019; 2019/2020; 2020/2021).
Our main goal is to describe and model the energy transfer from laser to particles, from the transparent to less transparent regime of laser-plasma interaction in the ultra-high intensity regime, and using the results obtained to optimize laser ion acceleration. We investigate the case of an ultra high intensity (1022 W/cm2) ultra short (20 fs) laser pulse interacting with a near-critical density plasma made of electrons and protons of density 5 nc (where nc = 1.1·1021 cm-3 is the critical density for a laser wavelength of 1 µm). Through 2D particle-in-cell (PIC) simulations, we study the optimal target thickness for the maximum conversion efficiency of the laser energy to particles. Theoretical modelling of the predominant laser-plasma interaction mechanisms predicts the particle energy and conversion efficiency optimization. Our studies led to an optimization of the target thickness for maximizing electron and proton acceleration.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST021  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST025 A High Power Prototype of a Harmonic Kicker Cavity kicker, cavity, operation, MMI 1749
 
  • G.-T. Park, G.A. Grose, J. Guo, A. OBrien, R.A. Rimmer, H. Wang, R.S. Williams
    JLab, Newport News, Virginia, USA
  • S.A. Overstreet
    ODU, Norfolk, Virginia, USA
 
  A harmonic kicker, a beam exchange device that can deflect the beam at an ultra-fast time scale (a few ns), has been developed in Jefferson Lab *, **. The high power prototype that can deliver more than a 100 kV kick at 7 kW was fabricated. The RF performance of cavity such as the harmonic resonant frequencies, kick profiles, it’s stability, and electric center is tested at bench. The cavity will eventually be tested with a beam at Upgraded Injector Test Facility (UITF) in Jefferson Lab. In this paper, we report some features of fabrication and bench test results. We also briefly describe our beam test plan in the future.
* G.Park, H.Wang, R.A.Rimmer, S. Wang, and J.Guo, THP092, Proceedings of IPAC2018, Vancouver, Canada (2018).
** G.Park, et al, WEPRBO99, Proceedings of IPAC2019, Melbourne, Australia (2019).
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST025  
About • Received ※ 11 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST029 First Start-to-End Simulations of the 6 GeV Laser-Plasma Injector at DESY laser, plasma, emittance, injection 1757
 
  • S.A. Antipov, I.V. Agapov, R. Brinkmann, A. Ferran Pousa, M.A. Jebramcik, A. Martinez de la Ossa, M. Thévenet
    DESY, Hamburg, Germany
 
  DESY is studying the feasibility of a 6 GeV laser-plasma injector for top-up operation of its future flagship synchrotron light source PETRA IV. A potential design of such an injector involves a single plasma stage, a beamline for beam capture and phase space manipulation, and a X-band rf energy compressor. Numerical tracking with realistic beam distributions shows that an energy variation below 0.1%, rms and a transverse emittance about 1 nm-rad, rms can be achieved under realistic timing, energy, and pointing jitters. PETRA IV injection efficiency studies performed with a conservative 5% beta-beating indicate negligible beam losses for the simulated beams during top-up. Provided the necessary progress on high-power lasers and plasma cells, the laser plasma injector could become a competitive alternative to the conventional injector chain.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST029  
About • Received ※ 02 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST032 Status Report of the 50 MeV LPA-Based Injector at ATHENA for a Compact Storage Ring plasma, laser, storage-ring, target 1768
 
  • E. Panofski, C. Braun, J. Dirkwinkel, J.B. Gonzalez, T. Hülsenbusch, A.R. Maier, J. Osterhoff, G. Palmer, P.A. Walker, P. Winkler
    DESY, Hamburg, Germany
  • E. Bründermann, B. Härer, A.-S. Müller, A.I. Papash, C. Widmann
    KIT, Karlsruhe, Germany
  • T.F.J. Eichner, L. Hübner, S. Jalas, L. Jeppe, M. Kirchen, P. Messner, M. Schnepp, M. Trunk, C.M. Werle
    University of Hamburg, Hamburg, Germany
  • M. Kaluza, A. Sävert
    HIJ, Jena, Germany
 
  Laser-based plasma accelerators (LPA) have successfully demonstrated their capability to generate high-energy electron beams with intrinsically short bunch lengths and high peak currents at a setup with a small footprint. These properties make them attractive drivers for a broad range of different applications including injectors for rf-driven, ring-based light sources. In close collaboration the Deutsches Elektronen-Synchrotron (DESY), the Karlsruhe Institute of Technology (KIT) and the Helmholtz Institute Jena aim to develop a 50 MeV plasma injector and demonstrate the injection into a compact storage ring. This storage ring will be built within the project cSTART at KIT. As part of the ATHENA (Accelerator Technology HElmholtz iNfrAstructure) project, DESY will design, setup and operate a 50 MeV plasma injector prototype for this endeavor. This contribution gives a status update of the 50 MeV LPA-based injector and presents a first layout of the prototype design at DESY in Hamburg.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST032  
About • Received ※ 07 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 14 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST034 Magnetic Characterization of a Superconducting Transverse Gradient Undulator for Compact Laser Wakefield Accelerator-Driven FELs undulator, laser, FEL, wakefield 1772
 
  • K. Damminsek, A. Bernhard, H.J. Cha, A.W. Grau, A.-S. Müller, M.S. Ning, Y. Tong
    KIT, Karlsruhe, Germany
  • S.C. Richter
    CERN, Meyrin, Switzerland
  • R. Rossmanith
    DESY, Hamburg, Germany
 
  Funding: Federal Ministry of Education and Research of Germany and the Development and Promotion of Science and Technology Talents Project (DPST)
A transverse gradient undulator (TGU) is a key component compensating for the relatively large energy spread of Laser Wakefield Accelerator (LWFA)-generated electron beams for realizing a compact Free Electron Laser (FEL). A superconducting TGU with 40 periods has been fabricated at the Karlsruhe Institute of Technology (KIT). In this contribution, we report that the superconducting TGU has been commissioned with nominal operational parameters at an off-line test bench. An experimental set-up for mapping the magnetic field on a two-dimensional grid in the TGU gap has been employed for the magnetic characterization. We show the first preliminary results of these measurements showing the longitudinal quality, the transverse gradient and the transient behaviour of the superconducting TGU field.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST034  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST035 Spectroscopic Measurements as Diagnostic Tool for Plasma-Filled Capillaries plasma, acceleration, laser, GUI 1776
 
  • S. Arjmand, L. Crincoli, D. Pellegrini
    INFN/LNF, Frascati, Italy
  • M.P. Anania, A. Biagioni, G. Costa, M. Ferrario, M. Galletti, V.L. Lollo, R. Pompili
    LNF-INFN, Frascati, Italy
  • M. Del Franco
    ENEA C.R. Frascati, Frascati (Roma), Italy
  • D. Giulietti
    UNIPI, Pisa, Italy
  • A. Zigler
    The Hebrew University of Jerusalem, The Racah Institute of Physics, Jerusalem, Israel
 
  The research concerns the study of the plasma sources for plasma-based accelerators (PBAs) at the SPARC_LAB test-facility (LNF-INFN). The interest in compact accelerators, overcoming the gigantism of the conventional radio-frequency (RF) accelerators, is growing in High Energy Physics. The plasma-based accelerating gradients can attain the GV/m scale. At the SPARC_LAB test-facility, a plasma device is under development. It consists of a capillary in which one or more inlets inject neutral gas (Hydrogen), ionized by a high-voltage (HV) discharge. Electron density has been measured as a function of time through the Stark broadening profiles of the Balmer line.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST035  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST039 Mapping Charge Capture and Acceleration in a Plasma Wakefield of a Proton Bunch Using Variable Emittance Electron Beam Injection plasma, experiment, wakefield, emittance 1780
 
  • E. Granados, A.-M. Bachmann, E. Chevallay, S. Döbert, V.N. Fedosseev, F. Friebel, S.J. Gessner, E. Gschwendtner, S.Y. Kim, S. Mazzoni, M. Turner, L. Verra
    CERN, Meyrin, Switzerland
  • A.-M. Bachmann, L. Verra
    MPI, Muenchen, Germany
  • S.Y. Kim
    UNIST, Ulsan, Republic of Korea
  • S.Y. Kim
    ANL, Lemont, Illinois, USA
  • J.T. Moody
    MPI-P, München, Germany
 
  In the Phase 2 of the AWAKE first experimental run (from May to November 2018), an electron beam was used to probe and test proton-driven wakefield accelera-tion in a rubidium plasma column. The witness electron bunches were produced using an RF-gun equipped with a Cs2Te photocathode illuminated by a tailorable ultrafast ultraviolet (UV) laser pulse. The construction of the UV beam optical system enabled appropriate transverse beam shaping and control of its pulse duration, size, and position on the photocathode, as well as time delay with respect to the ionizing laser pulse that seeds the plasma wakefields in the proton bunches. Variable photocathode illumination provided the required flexibility to produce electron bunches with variable charge, emittance, and injection trajectory into the plasma column. In this work, we analyze the overall charge capture and shot-to-shot reproducibility of the proton-driven plasma wakefield accelerator with various UV illumination and electron bunch injection parameters.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST039  
About • Received ※ 23 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST040 Comparing Methods of Recovering Gamma Energy Distributions from PEDRO Spectrometer Responses photon, positron, site, scattering 1784
 
  • M.H. Oruganti, B. Naranjo, J.B. Rosenzweig, M. Yadav
    UCLA, Los Angeles, California, USA
 
  To calculate the energy levels of the photons emitted from high-energy particle interactions, the new pair spectrometer (PEDRO) channels the photons through several Beryllium nuclear fields to produce electron-positron pairs through the nuclear field interaction. This project compared several methods of reconstruction and determined which best predicts original energy distributions based on simulated spectra. These methods included using Maximum Likelihood Estimation, Machine Learning, and directly analyzing a response matrix that modeled PEDRO’s response to any photon energy distribution. We report that performing the direct analysis, also known as QR decomposition, on a PEDRO-generated spectrum provides by far the most accurate calculation of the spectrum’s original energy distribution. These methods were tested against results from experimental cases, including Nonlinear Compton Scattering and Filamentation.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST040  
About • Received ※ 15 June 2022 — Revised ※ 01 July 2022 — Accepted ※ 08 July 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST041 Physical Aspects of Collinear Laser Injection at SLAC FACET-II E-310: Trojan Horse Experiment plasma, radiation, experiment, laser 1787
 
  • M. Yadav, O. Apsimon, E. Kukstas, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • C.E. Hansel, P. Manwani, B. Naranjo, J.B. Rosenzweig
    UCLA, Los Angeles, USA
  • B. Hidding
    USTRAT/SUPA, Glasgow, United Kingdom
 
  Funding: This work was performed with support of the US Department of Energy, Division of High Energy Physics, un-der Contract No. DE-SC0009914, and the STFC grant ST/P006752/1.
The Facility for Advanced Accelerator Experimental Tests (FACET-II) is a test accelerator infrastructure at SLAC dedicated to the research and development of advanced accelerator technologies. We performed simulations of electron beam driven wakefields, with collinear lasers used for ionization injection of electrons. We numerically generated a witness beam using the OSIRIS code in an up ramp plasma as well as uniform plasma regimes. We report on challenges and details of the E-310 experiment which aims to demonstrate this plasma photocathode injection at FACET-II. We examine the phenomena beam hosing and drive beam depletion. Details of the witness beam generated are discussed. Computation of betatron-radiation X-ray spatial distribution and critical energy are done for FACET-II low emittance beams.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST041  
About • Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 21 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST042 Radiation Diagnostics for AWA and FACET-II Flat Beams in Plasma plasma, radiation, betatron, emittance 1791
 
  • M. Yadav, O. Apsimon, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • H.S. Ancelin, G. Andonian, P. Manwani, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
 
  Funding: This work was performed with support of the US Department of Energy, Division of High Energy Physics, under Contract No. DE-SC0009914, DE-SC0017648 - AWA and STFC grant ST/P006752/1 ,
In energy beam facilities like FACET and AWA, beams with highly asymmetric emittance are of interest because they are the preferred type of beam for linear colliders. That is ultimately the motivation: building a plasma based LC. In this case, the blowout region is no longer symmetric around an axis is not equal in the two transverse planes. Focusing is required to keep the particles within the tight apertures and characterizing these accelerators shows the benefits of employing ultra low beam emittances. Beams with high charge and high emittance ratios in excess of 100:1 are available at AWA. If the focusing will not be equal, then we will have different radiation signatures for the flat and symmetric beams in plasma. We use OSIRIS particle-in-cell codes to compare various scenarios including a weak blowout and a strong blowout. Further, we determine the radiation generated in the system by importing particle trajectories into a Liénard Weichert code. We discuss future steps towards full diagnostics of flat beams using radiation.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST042  
About • Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 20 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST043 An Effective-Density Model for Accelerating Fields in Laser-Graphene Interactions laser, plasma, target, simulation 1795
 
  • C. Bonțoiu, O. Apsimon, E. Kukstas, C.P. Welsch, M. Yadav
    The University of Liverpool, Liverpool, United Kingdom
  • A. Bonatto
    Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
  • J. Resta-López
    ICMUV, Paterna, Spain
  • G.X. Xia
    UMAN, Manchester, United Kingdom
 
  Funding: This work was supported by STFC Liverpool Centre for Doctoral Training on Data Intensive Science (LIV. DAT)
With the advancement of high-power UV laser technology, the use of nanostructures for particle acceleration attracts renewed interest due to its possibility of achieving TV/m accelerating gradients in solid state plasmas. Electron acceleration in ionized materials such as carbon nanotubes and graphene is currently considered as a potential alternative to the usual laser wakefield acceleration (LWFA) schemes. An evaluation of the suitability of a graphene target for LWFA can be carried out using an effective density model, thus replacing the need to model each layer. We present a 2D evaluation of the longitudinal electric field driven by a short UV laser pulse in a multi-layer graphene structure, showing that longitudinal fields of ~5 TV/m are achievable.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST043  
About • Received ※ 20 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOST045 Simulating Enhanced Focusing Effects of Ion Motion in Adiabatic Plasmas plasma, focusing, emittance, experiment 1798
 
  • D.R. Chow, C.E. Hansel, P. Manwani, J.B. Rosenzweig, M. Yadav
    UCLA, Los Angeles, USA
  • Ö. Apsimon, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: This work was performed with support of the US Department of Energy, Division of High Energy Physics, under Contract No. DE-SC0009914, and the STFC Liverpool Centre for Doctoral Training on Data Intensive Science (LIV. DAT) under grant agreement ST/P006752/1.
The FACET-II facility offers the unique opportunity to study low emittance, GeV beams and their interactions with high density plasmas in plasma wakefield acceleration (PWFA) scenarios. One of the experiments relevant to PWFA research at FACET-II is the ion collapse experiment E-314, which aims to study how ion motion in a PWFA can produce dual-focused equilibrium. As nonlinear focusing effects due to nonuniform ion distributions have not been extensively studied; we explore the difficulties of inducing ion motion in an adiabatic plasma and examines the effect an ion column has on beam focusing. A case study is performed on a system containing a plasma lens and adiabatic PWFA. Ions in the lens section are assumed to be static, while simulations of an adiabatic matching section are modified to include the effects of ion column collapse and their nonlinear focusing fields. Using the parameters of the FACET-II beam, we find that a collapsed ion column amplifies the focusing power of a plasma without compromising emittance preservation. This led to a spot size orders of magnitude less than that of a simply matched beam.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST045  
About • Received ※ 07 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 25 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT001 NICA Ion Collider and Plans of Its First Operations booster, collider, injection, luminosity 1819
 
  • E. Syresin, O.I. Brovko, A.V. Butenko, A.R. Galimov, E.V. Gorbachev, V. Kekelidze, H.G. Khodzhibagiyan, S.A. Kostromin, V.A. Lebedev, I.N. Meshkov, A.V. Philippov, A.O. Sidorin, G.V. Trubnikov, A. Tuzikov
    JINR, Dubna, Moscow Region, Russia
 
  The Nuclotron-based Ion Collider fAcility (NICA) is under assembling in JINR. The NICA goals are providing of colliding beams for studies of hot and dense strongly interacting baryonic matter and spin physics. The heavy ion injection complex of Collider NICA consisting from following accelerators: new acting heavy ion linac HILAC with RFQ and IH DTL sections at energy 3.2 MeV/u, new acting superconducting Booster synchrotron at energy up 600 MeV/u, acting superconducting synchrotron Nuclotron at gold ion energy 3.9 GeV/n, will starts operation with first ion beams in beginning of 2022. The assembling of two Collider storage rings with two interaction points was done in December 2021. The status of acceleration complex NICA and plans of its first operation is under discussion.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT001  
About • Received ※ 30 May 2022 — Accepted ※ 12 June 2022 — Issue date ※ 17 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT003 Challenges of Low Energy Hadron Colliders collider, luminosity, emittance, operation 1825
 
  • G.V. Trubnikov, V.A. Lebedev
    JINR, Dubna, Moscow Region, Russia
  • A.V. Butenko, S.A. Kostromin, I.N. Meshkov, A.V. Philippov, A.O. Sidorin, E. Syresin, A. Tuzikov
    JINR/VBLHEP, Dubna, Moscow region, Russia
 
  NICA collider complex is under construction at JINR. The initial configuration of the collider will perform collisions of fully stripped heavy ions, 209 Bi and others, for a study of phase transition in the quark-gluon plasma in the energy range 1/4.5 GeV/u per beam. Commissioning of the collider injection chain has been recently started. The complex includes 2 linacs, 2 Booster synchrotrons (Booster and Nuclotron to support the beam injection to the collider), and 2 collider rings of 503 m circumference. The design luminosity is ~1027 1/(cm*s) at 4.5 GeV/u. The heavy ions are generated in the ESIS-type ion source with intensity ~10 9 /pulse. Then they are accelerated into the linac and Booster and directed to stripping target. Next, fully stripped ions are accelerated in the Nuclotron and injected into Collider. The electron and stochastic cooling are used in each of the collider rings to support beam accumulation and to prevent the emittance growth due to intrabeam scattering. Three RF systems are used for longitudinal phase space manipulations. An achievement of design luminosity requires overcoming many technological and beam physics problems which are discussed in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT003  
About • Received ※ 30 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT023 A Design of ILC E-Driven Positron Source positron, cavity, linac, acceleration 1889
 
  • M. Kuriki, S. Konno, Z.J. Liptak
    HU/AdSM, Higashi-Hiroshima, Japan
  • M.K. Fukuda, T. Omori, Y. Seimiya, J. Urakawa, K. Yokoya
    KEK, Ibaraki, Japan
  • S. Kashiwagi
    Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
  • H. Tajino
    HU ADSE, Hiroshima, Japan
  • T. Takahashi
    Hiroshima University, Graduate School of Science, Higashi-Hiroshima, Japan
 
  ILC is an electron-positron linear collider based on Superconducting linear accelerator. Linear collider is an only solution to realinze high energy electron-positron collision beyond the limit of synchrotron radiation energy loss by ring colliders. Beam current of injector of linear colliders is much larger than that of ring colliders because the beam is not reusable. Providing an enough amount of particles, especially positron is a technical issue. In this article, we present a design of electron driven positron source for ILC. After optimizations, the system design is established with an enough technical margin, e.g. avoiding potential damage on the production target.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT023  
About • Received ※ 20 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT026 Possibilities for Upgrading to Polarized a SuperKEKB polarization, experiment, lattice, cathode 1901
 
  • Z.J. Liptak
    HU/AdSM, Higashi-Hiroshima, Japan
 
  The SuperKEKB accelerator is currently in operation in Tsukuba, Japan, with a planned long shutdown in 2026. Among the possible upgrades being considered during this period is the change to a polarized electron beam in the High Energy Ring. Such a change would require modifications in the source generation and transport, geometrical and lattice variations to provide spin rotation, and polarimetry. A Polarized SuperKEKB Working Group has been formed from members of the Belle II experiment and the SuperKEKB accelerator team to investigate the possibilities and challenges of these modifications. This presentation lays out the goals and motivations of polarizing the electron beam, considers the necessary changes to the existing accelerator and their feasibility and reports progress in investigations to this point.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT026  
About • Received ※ 12 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT032 Summary of the 3-year Beam Energy Scan II operation at RHIC luminosity, operation, space-charge, cavity 1908
 
  • C. Liu, P. Adams, E.N. Beebe, S. Binello, I. Blackler, M. Blaskiewicz, K.A. Brown, D. Bruno, B.D. Coe, K.A. Drees, A.V. Fedotov, W. Fischer, C.J. Gardner, C.E. Giorgio, X. Gu, T. Hayes, K. Hock, H. Huang, R.L. Hulsart, T. Kanesue, D. Kayran, N.A. Kling, B. Lepore, Y. Luo, D. Maffei, G.J. Marr, A. Marusic, K. Mernick, R.J. Michnoff, M.G. Minty, J. Morris, C. Naylor, S. Nemesure, M. Okamura, I. Pinayev, S. Polizzo, D. Raparia, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, S. Seletskiy, F. Severino, T.C. Shrey, P. Thieberger, M. Valette, A. Zaltsman, I. Zane, K. Zeno, W. Zhang
    BNL, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Beam Energy Scan phase II (BES-II) operation in the Relativistic Heavy Ion Collider (RHIC), aiming to explore the phase transition between quark-gluon plasma (QGP) and hadronic gas, exceeded the goal of a four-fold increase in the average luminosity over the range of five gold beam energies (9.8, 7.3, 5.75, 4.59 and 3.85 GeV/nucleon) compared to those achieved during Beam Energy Scan phase I (BES-I). We will present the achievements in BES-II together with a summary of the measures taken to improve RHIC performance in the presence of several beam dynamics effects, and details on improvements made during the operation at 3.85 GeV/nucleon in 2021.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT032  
About • Received ※ 06 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT033 Report of RHIC Beam Operation in 2021 operation, luminosity, target, experiment 1912
 
  • C. Liu, P. Adams, E.N. Beebe, S. Binello, I. Blackler, M. Blaskiewicz, K.A. Brown, D. Bruno, B.D. Coe, K.A. Drees, A.V. Fedotov, W. Fischer, C.J. Gardner, C.E. Giorgio, X. Gu, T. Hayes, K. Hock, H. Huang, R.L. Hulsart, T. Kanesue, D. Kayran, N.A. Kling, B. Lepore, Y. Luo, D. Maffei, G.J. Marr, A. Marusic, K. Mernick, R.J. Michnoff, M.G. Minty, J. Morris, C. Naylor, S. Nemesure, M. Okamura, I. Pinayev, S. Polizzo, D. Raparia, G. Robert-Demolaize, T. Roser, J. Sandberg, V. Schoefer, S. Seletskiy, F. Severino, T.C. Shrey, P. Thieberger, M. Valette, A. Zaltsman, I. Zane, K. Zeno, W. Zhang
    BNL, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The first priority of RHIC operation in 2021 was the Au+Au collisions at 3.85 GeV/nucleon, which is the lowest energy to complete the 3-year Beam Energy Scan II physics program, with RF-based electron cooling. In addition, RHIC also operated for several other physics programs including fixed target experiments, O+O at 100 GeV/nucleon, Au+Au at 8.65 GeV/nucleon, and d+Au at 100 GeV/nucleon. This report presents the operational experience and the results from RHIC operation in 2021. With Au+Au collisions at 3.85 GeV/nucleon reported in a separate report, this paper focuses on the operation conditions for the other programs mentioned above.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT033  
About • Received ※ 06 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT034 Reconfiguration of RHIC Straight Sections for the EIC hadron, focusing, quadrupole, kicker 1916
 
  • C. Liu, J.S. Berg, D. Bruno, C. Cullen, K.A. Drees, W. Fischer, X. Gu, R.C. Gupta, D. Holmes, R.F. Lambiase, H. Lovelace III, C. Montag, S. Peggs, V. Ptitsyn, G. Robert-Demolaize, R. Than, J.E. Tuozzolo, M. Valette, S. Verdú-Andrés, D. Weiss, D. Xu
    BNL, Upton, New York, USA
  • B. Bhandari, F. Micolon, N. Tsoupas
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
  • B.R. Gamage, T. Satogata, W. Wittmer
    JLab, Newport News, Virginia, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 and Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177.
The Electron-Ion Collider (EIC) will be built in the existing Relativistic Heavy Ion Collider (RHIC) tunnel with the addition of electron acceleration and storage rings. The two RHIC rings will be reconfigured as a single Hadron Storage Ring (HSR) for accelerating and storing ion beams. The proton beam energy will be raised from 255 to 275 GeV to achieve the desired center-of-mass energy range: 20’140 GeV. It is also mandatory to operate the HSR with a constant revolution frequency over a large energy range (41’275 GeV for protons) to synchronize with the Electron Storage Ring (ESR). These and other requirements/challenges dictate modifications to RHIC accelerators. This report gives an overview of the modifications to the RHIC straight sections together with their individual challenges.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT034  
About • Received ※ 06 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT035 Optics for Strong Hadron Cooling in EIC HSR-IR2 hadron, optics, kicker, cavity 1920
 
  • S. Peggs, W.F. Bergan, D. Bruno, Y. Gao, D. Holmes, R.F. Lambiase, C. Liu, H. Lovelace III, G.J. Mahler, V. Ptitsyn, G. Robert-Demolaize, R. Than, J.E. Tuozzolo, E. Wang, D. Weiss, D. Xu
    BNL, Upton, New York, USA
  • S.V. Benson, T.J. Michalski
    JLab, Newport News, Virginia, USA
  • F. Micolon
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC001 2704, and by Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177.
Insertion Region 2 (IR2) of the Relativistic Heavy Ion Collider will be modified to accommodate a Strong Hadron Cooling facility in the Hadron Storage Ring (HSR) of the Electron-Ion Collider (EIC). This paper describes the current proof-of-principle design of HSR-IR2 - layout, optical performance, design methodology, and engineering requirements. It also describes the challenges and opportunities in the future development of the HSR-IR2 design, in order to further optimize Strong Hadron Cooling performance.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT035  
About • Received ※ 02 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT036 Dependence of Beam Size Growth on Macro-Particle’s Initial Actions in Strong-Strong Beam-Beam Simulation for the Electron-Ion Collider simulation, proton, emittance, collider 1924
 
  • Y. Luo, J.S. Berg, M. Blaskiewicz, W. Fischer, X. Gu, J. Kewisch, H. Lovelace III, C. Montag, S. Peggs, V. Ptitsyn, F.J. Willeke, D. Xu
    BNL, Upton, New York, USA
  • B.R. Gamage, H. Huang, E.A. Nissen, T. Satogata
    JLab, Newport News, Virginia, USA
  • Y. Hao
    FRIB, East Lansing, Michigan, USA
  • G.H. Hoffstaetter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 and Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177.
The Electron-Ion Collider (EIC) presently under construction at Brookhaven National Laboratory will collide polarized high energy electron beams with hadron beams with design luminosities up to 1×1034cm-2s-1 in the center mass energy range of 20-140 GeV. We simulated the planned electron-proton collision of flat beams with Particle-In-Cell (PIC) based Poisson solver in strong-strong beam-beam simulation. We observed a much larger proton emittance growth rate than that from weak-strong simulation. To understand the numerical noises further, we calculate the beam size growth rate of macro-particles as function of their initial longitudinal and transverse actions. This method is applied to both strong-strong and weak-strong simulations. The purpose of this study is to identify which group of macro-particles contributes most of the artificial emittance growth in strong-strong beam-beam simulation.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT036  
About • Received ※ 22 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT037 Dynamic Aperture Evaluation for EIC Hadron Storage Ring with Crab Cavities and IR Nonlinear Magnetic Field Errors dynamic-aperture, proton, cavity, simulation 1927
 
  • Y. Luo, J.S. Berg, W. Fischer, X. Gu, H. Lovelace III, C. Montag, S. Peggs, V. Ptitsyn, H. Witte, D. Xu
    BNL, Upton, New York, USA
  • Y. Hao
    FRIB, East Lansing, Michigan, USA
  • V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
  • T. Satogata
    JLab, Newport News, Virginia, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 and Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177.
The electron ion collider (EIC) presently under construction at Brookhaven National Laboratory will collider polarized high energy electron beams with hadron beams with luminosities up to 1034 cm-2s-1 in the center mass energy range of 20-140 GeV. In this article, we evaluate the dynamic aperture of the Hadron Storage Ring (HSR) with symplectic element-by-element tracking. Crab cavities, nonlinear magnetic field errors, and weak-strong beam-beam interaction are included. We compared the dynamic aperture from head-on collision to crossing-angle collision and found the reason for the dynamic aperture drop. We also studied the field error tolerances for IR magnets and for some particular magnets.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT037  
About • Received ※ 22 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT038 Summary of Numerical Noise Studies for Electron-Ion Collider Strong-Strong Beam-Beam Simulation proton, simulation, emittance, collider 1931
 
  • Y. Luo, J.S. Berg, M. Blaskiewicz, W. Fischer, X. Gu, J. Kewisch, H. Lovelace III, C. Montag, S. Peggs, V. Ptitsyn, F.J. Willeke, D. Xu
    BNL, Upton, New York, USA
  • B.R. Gamage, H. Huang, E.A. Nissen, T. Satogata
    JLab, Newport News, Virginia, USA
  • G.H. Hoffstaetter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy
The Electron-Ion Collider (EIC) presently under construction at Brookhaven National Laboratory will collide polarized high energy electron beams with hadron beams, reaching luminosities up to 1×1034cm-2s-1 in center mass energy range of 20-140 GeV. We studied the planned electron-proton collisions using a Particle-In-Cell (PIC) based Poisson solver in strong-strong beam-beam simulation. We observed a much larger proton emittance growth rate than in weak-strong simulation. To understand the numerical noise and its impact on strong-strong simulation results, we carried out extensive studies to identify all possible causes for artificial emittance growth and quantify their contributions. In this article, we summarize our study activities and findings. This work will help us better understand the simulated emittance growth and the limits of the PIC based strong-strong beam-beam simulation.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT038  
About • Received ※ 19 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT040 Numerical Noise Error of Particle-In-Cell Poisson Solver for a Flat Gaussian Bunch simulation, proton, emittance, collider 1939
 
  • Y. Luo, J.S. Berg, M. Blaskiewicz, W. Fischer, X. Gu, H. Lovelace III, C. Montag, R.B. Palmer, S. Peggs, V. Ptitsyn, F.J. Willeke, D. Xu
    BNL, Upton, New York, USA
  • Y. Hao
    FRIB, East Lansing, Michigan, USA
  • H. Huang, E.A. Nissen, T. Satogata
    JLab, Newport News, Virginia, USA
  • V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy and Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177.
The Electron-Ion Collider (EIC) presently under construction at Brookhaven National Laboratory will collider polarized high energy electron beams with hadron beams with luminosity up to 1×1034cm-2s-1 in the center mass energy range of 20-140 GeV. We simulated the planned electron-proton collision of flat beams with Particle-In-Cell (PIC) based Poisson solver in strong-strong beam-beam simulation. We observed a much larger proton emittance growth rate than that from weak-strong simulation. To better understand the emittance growth rate from the strong-strong simulation, we compare the beam-beam kicks between the PIC method and the analytical calculation and calculate the RMS variation in beam-beam kicks among 1000 sets of random Gaussian particle distributions. The impacts of macro-particle number, grid number, and bunch flatness are also studied.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT040  
About • Received ※ 23 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT041 Strong-Strong Simulations of Coherent Beam-Beam Effects in the EIC proton, luminosity, simulation, resonance 1942
 
  • J. Qiang
    LBNL, Berkeley, California, USA
  • Y. Hao
    FRIB, East Lansing, Michigan, USA
  • Y. Luo, C. Montag, F.J. Willeke, D. Xu
    BNL, Upton, New York, USA
 
  The high luminosity electron ion collider (EIC) will provide great opportunities in nuclear physics study and is under active design. The coherent effects due to the beam-beam interaction of two colliding beams can cause beam size blow-up and degrade the luminosity in the EIC. In this paper, we report on the study of coherent beam-beam effects in the EIC design using self-consistent strong-strong simulations. These simulations show the coherent dipole and quadrupole mode instabilities in the tune working point scan and bunch intensity scan.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT041  
About • Received ※ 18 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT042 Designing the EIC Electron Storage Ring Lattice for a Wide Energy Range solenoid, dipole, lattice, quadrupole 1946
 
  • D. Marx, J.S. Berg, J.S. Berg, J. Kewisch, Y. Li, Y. Li, C. Montag, V. Ptitsyn, V. Ptitsyn, S. Tepikian, F.J. Willeke, F.J. Willeke, D. Xu
    BNL, Upton, New York, USA
  • Y. Cai, Y.M. Nosochkov
    SLAC, Menlo Park, California, USA
  • B.R. Gamage, V.S. Morozov, V.S. Morozov
    JLab, Newport News, Virginia, USA
  • G.H. Hoffstaetter, G.H. Hoffstaetter, D. Sagan, D. Sagan, J.E. Unger
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
  • M.G. Signorelli
    Cornell University, Ithaca, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC, under Contract No. DE-SC0012704, by Jefferson Science Associates, LLC, under Contract No. DE-AC05-06OR23177, by UT-Battelle, LLC, under contract DE-AC05-00OR22725, and by SLAC under Contract No. DE-AC02-76SF00515 with the U.S. Department of Energy.
The Electron-Ion Collider (EIC) will collide electrons with hadrons at center-of-mass energies up to 140 GeV (in the case of electron-proton collisions). A 3.8-kilometer electron storage ring is being designed, which will store electrons with a range of energies up to 18 GeV for collisions at one or two interaction points. At energies up to 10 GeV the arcs will be tuned to provide 60 degree phase advance per cell in both planes, whereas at top energy of 18 GeV a 90 degree phase advance per cell will be used, which largely compensates for the horizontal emittance increase with energy. The optics must be matched at three separate energies, and the different phase-advance requirements in both the arc cells and the straight sections make this challenging. Moreover, the spin rotators must fulfill requirements for polarization and spin matching at widely different energies while satisfying technical constraints. In this paper these challenges and proposed solutions are presented and discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT042  
About • Received ※ 16 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 25 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT043 Dynamic Aperture of the EIC Electron Storage Ring sextupole, lattice, optics, quadrupole 1950
 
  • Y.M. Nosochkov, Y. Cai
    SLAC, Menlo Park, California, USA
  • J.S. Berg, J. Kewisch, Y. Li, D. Marx, C. Montag, S. Tepikian, H. Witte
    BNL, Upton, New York, USA
  • G.H. Hoffstaetter, J.E. Unger
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  Funding: Work supported by the Department of Energy Contract DE-AC02-76SF00515, by Brookhaven Science Associates, LLC under Contract DE-SC0012704, and by the Ernest Courant Traineeship in Accelerator Science and Technology Award No. DE-SC0020375.
The Electron Ion Collider (EIC) is under design at Brookhaven National Laboratory. The EIC aims at providing high luminosity and high polarization collisions for a large range of beam energies. Dynamic aperture (DA) of the EIC Electron Storage Ring (ESR) must be sufficiently large in both transverse and momentum dimensions. The latter is a challenge due to low-beta optics in up to two interaction regions (IR). We have developed an advanced technique for efficient non-linear chromaticity compensation compatible with the different ESR lattice configurations at different energies. The solution for the most challenging lattice with two IRs at 18 GeV is presented. The lattice is then evaluated with magnet errors, where the error tolerances are determined for reaching the desired DA.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT043  
About • Received ※ 08 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 01 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT044 Electron-Ion Collider Design Status hadron, storage-ring, collider, simulation 1954
 
  • C. Montag, E.C. Aschenauer, G. Bassi, J. Beebe-Wang, J.S. Berg, M. Blaskiewicz, J.M. Brennan, S.J. Brooks, K.A. Brown, Z.A. Conway, K.A. Drees, A.V. Fedotov, W. Fischer, C. Folz, X. Gu, R.C. Gupta, Y. Hao, C. Hetzel, D. Holmes, H. Huang, J.P. Jamilkowski, J. Kewisch, Y. Li, C. Liu, H. Lovelace III, Y. Luo, G.J. Mahler, D. Marx, F. Méot, M.G. Minty, S.K. Nayak, R.B. Palmer, B. Parker, S. Peggs, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, M.P. Sangroula, S. Seletskiy, K.S. Smith, S. Tepikian, R. Than, P. Thieberger, N. Tsoupas, J.E. Tuozzolo, E. Wang, D. Weiss, F.J. Willeke, H. Witte, Q. Wu, D. Xu, W. Xu, A. Zaltsman
    BNL, Upton, New York, USA
  • S.V. Benson, B.R. Gamage, J.M. Grames, T.J. Michalski, E.A. Nissen, J.P. Preble, R.A. Rimmer, T. Satogata, A. Seryi, M. Wiseman, W. Wittmer
    JLab, Newport News, Virginia, USA
  • A. Blednykh, D.M. Gassner, B. Podobedov, S. Verdú-Andrés
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
  • Y. Cai, Y.M. Nosochkov, G. Stupakov, M.K. Sullivan
    SLAC, Menlo Park, California, USA
  • E. Gianfelice-Wendt
    Fermilab, Batavia, Illinois, USA
  • G.H. Hoffstaetter, D. Sagan, J.E. Unger
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • F. Lin, V.S. Morozov
    ORNL RAD, Oak Ridge, Tennessee, USA
  • M.G. Signorelli
    Cornell University, Ithaca, New York, USA
 
  Funding: Work supported under Contract No. DE-SC0012704, Contract No. DE-AC05-06OR23177, Contract No. DE-AC05-00OR22725, and Contract No. DE-AC02-76SF00515 with the U.S. Department of Energy.
The Electron-Ion Collider (EIC) is being designed for construction at Brookhaven National Laboratory. Activities have been focused on beam-beam simulations, polarization studies, and beam dynamics, as well as on maturing the layout and lattice design of the constituent accelerators and the interaction region. The latest design advances will be presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT044  
About • Received ※ 03 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT045 Transverse Electron Beam Tails and Beam Lifetime in the EIC Electron Storage Ring simulation, proton, vacuum, storage-ring 1958
 
  • C. Montag
    BNL, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704.
While for most storage ring design activities it is sufficient to assume a Gaussian distribution of the beam particles, a more detailed prediction of the population in the transverse tails is necessary to predict the beam lifetime in a given aperture. Dominant processes that result in non-Gaussian distributions are the beam-beam interaction in a collider as well as beam-gas scattering. Simulations to determine the required apertures and vacuum levels in the EIC electron storage ring will be presented.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT045  
About • Received ※ 03 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 28 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT047 Beam Optics of the Injection/Extraction and Beam Transfer in the Electron Rings of the EIC Project injection, extraction, optics, kicker 1964
 
  • N. Tsoupas, D. Holmes, C. Liu, C. Montag, V. Ptitsyn, V.H. Ranjbar, J. Skaritka, J.E. Tuozzolo, E. Wang, F.J. Willeke
    BNL, Upton, New York, USA
  • B. Bhandari
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
The Electron-Ion Collider (EIC) project* has been approved by the Department of Energy to be built at the site of Brookhaven National Laboratory (BNL). The goal of the project is the collision of energetic (of many GeV/amu) ion species with electron bunches of energies up to 18 GeV. The EIC includes two electron rings, the Rapid Cycling Synchrotron (RCS) which accelerates the electron beam up to 18 GeV, and the Electron Storage Ring (ESR) which stores the electron beam for collisions with hadron beam, both to be installed in the same tunnel as the Hadron Storage Ring (HSR). This paper discusses the layout and the beam optics of the injection/extraction beam lines the electron rings and the beam optics of the transfer line from the RCS to the ESR ring.
* https://www.bnl.gov/eic/
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT047  
About • Received ※ 05 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT049 Beam-Beam Interaction for Tilted Storage Rings cavity, simulation, collider, storage-ring 1968
 
  • D. Xu, D. Holmes, C. Montag, F.J. Willeke
    BNL, Upton, New York, USA
  • Y. Hao
    FRIB, East Lansing, Michigan, USA
  • Y. Luo
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
  • J. Qiang
    LBNL, Berkeley, California, USA
 
  In the Electron-Ion Collider (EIC) design, to avoid vertical orbit bumps in the Electron Storage Ring (ESR) at some crossing points with Hadron Storage Ring (HSR) to preserve the electron polarization, we plan to tilt the ESR plane by 200 ’rad with an axis connecting IP6 and IP8. In this article, we study the beam-beam interaction when two rings are not in the same plane. The Lorentz boost formula is derived and the required vertical crabbing strength is calculated to compensate the dynamic effect The strong-strong simulations are performed to validate the theory.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT049  
About • Received ※ 16 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT054 Target Studies for the FCC-ee Positron Source target, radiation, positron, photon 1979
 
  • F. Alharthi, I. Chaikovska, R. Chehab, S. Ogur, A. Ushakov, S. Wallon
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • L. Bandiera, A. Mazzolari, M. Romagnoni, A.I. Sytov
    INFN-Ferrara, Ferrara, Italy
  • J. Diefenbach, W. Lauth
    IKP, Mainz, Germany
  • O. Khomyshyn
    Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
  • D.M. Klekots
    National Taras Shevchenko University of Kyiv, The Faculty of Physics, Kyiv, Ukraine
  • V.V. Mytrochenko
    NSC/KIPT, Kharkov, Ukraine
  • P. Sievers, Y. Zhao
    CERN, Meyrin, Switzerland
  • M. Soldani
    Università degli Studi di Ferrara, Ferrara, Italy
 
  FCC-ee injector study foresees 3.5~nC electron and positron bunches with 200 Hz repetition and 2 bunches per linac pulse at 6~GeV extraction energy. Regarding the possible options of positron production, we retain both of the conventional amorphous target and the hybrid target options. The hybrid scheme uses an intense photon production by 6 GeV electrons impinging on a crystal oriented along a lattice axis. In such a way, it involves two targets: a crystal as a photon radiator and an amorphous target-converter. Therefore, to avoid early failure or damage of the target, the candidate materials for the crystal and conversion targets have started to be tested by using the intense electron beam at Mainzer Mikrotron in Germany by the end of 2021. By manipulating the beam intensity, focusing, and chopping, a Peak Energy Deposition Density in the tested targets could be achieved close to that generated by the electron/photon beam in the FCC-ee positron target. Radiation-damage studies of the crystal sample have been also performed allowing estimating the effect on the photon enhancement used in the hybrid positron source.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT054  
About • Received ※ 16 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT063 The FCCee Pre-Injector Complex positron, linac, injection, collider 2007
 
  • P. Craievich, B. Auchmann, S. Bettoni, H.-H. Braun, M. Duda, D. Hauenstein, E. Hohmann, R. Ischebeck, P.N. Juranič, J. Kosse, G.L. Orlandi, M. Pedrozzi, J.-Y. Raguin, S. Reiche, S.T. Sanfilippo, M. Schaer, N. Vallis, R. Zennaro
    PSI, Villigen PSI, Switzerland
  • F. Alharthi, I. Chaikovska, S. Ogur
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • W. Bartmann, M. Benedikt, M.I. Besana, M. Calviani, S. Döbert, Y. Dutheil, O. Etisken, J.L. Grenard, A. Grudiev, B. Humann, A. Latina, A. Lechner, K. Oide, A. Perillo-Marcone, H.W. Pommerenke, R.L. Ramjiawan, Y. Zhao, F. Zimmermann
    CERN, Meyrin, Switzerland
  • A. De Santis
    INFN/LNF, Frascati, Italy
  • Y. Enomoto, K. Furukawa, K. Oide
    KEK, Ibaraki, Japan
  • O. Etisken
    Kirikkale University, Kirikkale, Turkey
  • C. Milardi
    LNF-INFN, Frascati, Italy
  • T.O. Raubenheimer
    SLAC, Menlo Park, California, USA
  • N. Vallis
    EPFL, Lausanne, Switzerland
 
  The international FCC study group published in 2019 a Conceptual Design Report for an electron-positron collider with a centre-of-mass energy from 90 to 365 GeV with a beam currents of up to 1.4 A per beam. The high beam current of this collider create challenging requirements on the injection chain and all aspects of the linac need to be carefully reconsidered and revisited, including the injection time structure. The entire beam dynamics studies for the full linac, damping ring and transfer lines are major activities of the injector complex design. A key point is that any increase of positron production and capture efficiency reduces the cost and complexity of the driver linac, the heat and radiation load of the converter system, and increases the operational margin. In this paper we will give an overview of the status of the injector complex design and introduce the new layout that has been proposed by the study group working in the context of the CHART collaboration. In this framework, furthermore, we also present the preliminary studies of the FCC-ee positron source highlighting the main requirements and constraints.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT063  
About • Received ※ 11 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOPT065 Simulations of the Upgraded Drive-Beam Photoinjector at the Argonne Wakefield Accelerator solenoid, emittance, laser, gun 2015
 
  • E.A. Frame, P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
  • S.Y. Kim, X. Lu, J.G. Power, D.S. Scott, E.E. Wisniewski
    ANL, Lemont, Illinois, USA
 
  Funding: Department of Energy
The Argonne Wakefield Accelerator (AWA) is planning to upgrade its photoinjector for the drive-beam accelerator. The main goal of the upgrade is to improve the beam brightness using a symmetrized RF-gun cavity. In the process, the photoinjector was reconfigured and some of the solenoid magnets redesigned. A challenging aspect of this optimization is that the injector should be able to produce bright low-charge (~1 nC) bunches while also being capable of operating at high-charge (~50 nC) bunches. This paper will discuss the optimization of the beam dynamics for the low- and high-charge cases and explore the performances of the proposed configuration using a model of the full AWA drive-beam beamline including 3D field maps for the external electromagnetic fields. The optimizations are performed with ASTRA and the DEAP toolbox and with OPAL.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT065  
About • Received ※ 08 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 16 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK002 Investigation, Simulation and First Measurements of a 2m Long Electron Column Trapped in a Gabor Lens Device experiment, plasma, focusing, diagnostics 2023
 
  • K.I. Thoma, M. Droba, O. Meusel
    IAP, Frankfurt am Main, Germany
 
  Various Gabor-Lenses (GL) were investigated at Goethe University. Confinement of sufficient electron densities (ne~1E15m3) were reached without any external source of electrons. Focusing of ion beams by low energy was demonstrated, long term stability and reproducibility were approved. Main differences compared to experiments and investigations of the pure non-neutral in Penning-Malmberg traps are higher residual gas pressure and therefore higher collision rates, higher bulk temperatures, self-sustaining electron production process, much higher evaporation cooling rate. GL2000 is a new 2m long device and was mainly designed for focusing of ion beams in energy ranges up to GeV but also for investigation of non-neutral plasma parameters. The confined electron column is much longer compared to previous constructed Lenses. This makes ion and hadron beam focussing much more efficient, in addition new physical phenomena can be expected and investigated. Simulation results of steady- and thermal equilibrium states with various external parameters and first measurements will be presented. The first operational tests show that it is possible to confine a two-meter long electron column.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK002  
About • Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK003 Status of the Development of the Electron Lens for Space Charge Compensation at GSI gun, cathode, solenoid, space-charge 2027
 
  • K. Schulte-Urlichs, D. Ondreka, P.J. Spiller, K.I. Thoma
    GSI, Darmstadt, Germany
  • M. Droba, T. Dönges, O. Meusel, H. Podlech
    IAP, Frankfurt am Main, Germany
 
  At GSI a prototype electron lens for space charge (SC) compensation is currently being designed and main components as the RF-modulated electron gun are already under commissioning. The goal of this project is the (partial) compensation of SC forces within the ion beam by an overlapping electron beam. This may help to increase the intensity of primary beams, especially in the FAIR facility and potentially all large synchrotrons operated at the SC limit. For an effective SC compensation, the generated electron beam needs to follow the transverse and longitudinal beam profile of the ion bunch structure. The requirements are maximum currents of 10 A and grid modulation to cover a broad frequency range from 400 kHz to 1 MHz. The RF-modulated electron gun was designed and manufactured in the scope of the ARIES collaboration and is currently being tested at the E-Lens Lab of Goethe University Frankfurt. A dedicated test bench was built for commissioning of the major e-lens components and diagnostics. In this contribution the overall set-up will be presented putting special emphasis on the beam dynamics and collector design as well as as well as simulation results of the electron gun.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK003  
About • Received ※ 18 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 07 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK014 Hadron Storage Ring 4 O’clock Injection Design and Optics for the Electron-Ion Collider injection, optics, septum, dipole 2068
 
  • H. Lovelace III, J.S. Berg, D. Bruno, C. Cullen, K.A. Drees, W. Fischer, X. Gu, R.C. Gupta, D. Holmes, R.F. Lambiase, C. Liu, C. Montag, S. Peggs, V. Ptitsyn, G. Robert-Demolaize, R. Than, J.E. Tuozzolo, M. Valette, D. Weiss
    BNL, Upton, New York, USA
  • B. Bhandari, F. Micolon, N. Tsoupas, S. Verdú-Andrés
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
  • B.R. Gamage, T. Satogata, W. Wittmer
    JLab, Newport News, Virginia, USA
 
  The Hadron Storage Ring (HSR) of the Electron-Ion Collider (EIC) will accelerate protons and heavy ions up to a proton energy of 275 GeV and an Au+79 110 GeV/u to collide with electrons of energies up to 18 GeV. To accomplish the acceleration process, the hadrons are pre-accelerated in the Alternating Gradient Synchrotron (AGS), extracted, and transferred to HSR for injection. The planned area for injection is the current Relativistic Heavy Ion Collider (RHIC) 4 o’clock straight section. To inject hadrons, a series of modifications must be made to the existing RHIC 4 o’clock straight section to accommodate for the 20 new ~18 ns injection kickers and a new injection septum, while providing sufficient space and proper beam conditions for polarimetry equipment. These modifications will be discussed in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK014  
About • Received ※ 02 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK015 The Electron-Ion Collider Hadron Storage Ring 10 O’clock Switchyard Design dipole, hadron, quadrupole, cavity 2071
 
  • H. Lovelace III, J.S. Berg, D. Bruno, C. Cullen, K.A. Drees, W. Fischer, X. Gu, R.C. Gupta, D. Holmes, R.F. Lambiase, C. Liu, C. Montag, S. Peggs, V. Ptitsyn, G. Robert-Demolaize, R. Than, J.E. Tuozzolo, M. Valette, D. Weiss
    BNL, Upton, New York, USA
  • B. Bhandari, F. Micolon, S. Verdú-Andrés
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
  • T. Satogata, W. Wittmer
    JLab, Newport News, Virginia, USA
 
  The Electron-Ion Collider (EIC) Hadron Storage Ring (HSR) will be composed of the current Relativistic Heavy Ion Collider (RHIC) yellow ring sextants with the exception of the 1 o’clock and the 11 o’clock arc. These two arcs use the existing blue ring inner (1 o’clock) and outer (11 o’clock) magnetic lattice for 275 GeV proton operation. The inner yellow 11 o’clock arc is used for 41 GeV energy operation. A switching magnet must be used to guide the hadron beam from the low and high energy arc respectively into the shared arc. This report provides the necessary lattice configuration, magnetic fields, and optics for the 10 o’clock utility straight section (USS) switchyard for both high and low energy configuration while providing the necessary space allocations and beam specifications for accelerator systems such as an additional radiofrequency cavity and beam dump.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK015  
About • Received ※ 01 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK016 Studies of ECR Plasmas and Materials Modification Using Low Energy Ion Beam Facility at IUAC plasma, ECR, ion-source, cyclotron 2074
 
  • P. Tripathi, P. Kumar, S.K. Singh
    IUAC, New Delhi, India
 
  The ECR ion sources are widely used to produce high intensities of highly charged positive ions*. To increase their performance further, several techniques are employed. The addition of a lighter gas into the main plasma (so-called gas mixing) shows a substantial effect on the charge state distribution of highly charged ions. Although many theoretical models were used to explain this gas mixing effect, yet it is not fully understood. The low energy ion beam facility (LEIBF) at Inter-University Accelerator Centre (IUAC), New Delhi, India, which comprises a 10 GHz all-permanent magnet NANOGAN ECR source placed on a high voltage platform (400kV) has been used to develop several plasmas for the physical understanding of ions production and their confinement in a strong magnetic field**. Further, the LEIBF allows us to extract ion beams from the plasma in the energy range of a few keV to tens of MeV for novel ion-matter interaction experiments. In this paper, the charge state distribution studies (relevant to gas mixing effect) of various atomic species at optimized ion source tuning parameters along with some interesting results on materials synthesis/modification using ion beams is presented.
*A. G. Drentje, Review of Scientific Instruments 74, 2631 (2003)/ **P. Kumar et al., Pramana 59(5):805-809(2002)/
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK016  
About • Received ※ 31 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 28 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK017 An Efficient H-/ D- Extraction in Neutral Beam Injection (NBI) Ion Sources extraction, simulation, plasma, ion-source 2078
 
  • V. Variale
    INFN-Bari, Bari, Italy
  • M. Cavenago
    INFN/LNL, Legnaro (PD), Italy
 
  Funding: INFN, DTT
The negative ion source development has reached performances very close to those required by the ITER project; see for example the test facility ELISE results*. A main residual problem seems to be the great amount of co-extracted electrons in the top part of the source. The introduction of a magnetic filter to remove the electrons from the extraction zone of the source causes ExB particle drifts (or shifts) which move both ions and electrons towards the top (or bottom depending on the B direction); in the top part the electron concentration and extracted current increase and that limits the extracted ion amount. In this contribution, as a possible solution, the application of a Planar Ion Funnel (PIF) extraction electric field configuration** on the source exit is proposed. The electric field line shape of PIF configuration, not only should break the perpendicularity between the magnetic filter B and the extraction electric field E in such a way to prevents the ExB particle drifts, but also should give a more efficient field shape for the H-/D- extraction. Preliminary simulations of D- and e- trajectories are presented to confirm the efficiency of the PIF system.
* B. Heinemann et al., Fusion Engineering and design (2021).
** A. Chaudhary et al., Rev. Sci. 85, 105101 (2014).
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK017  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK029 Advances in Low Energy Antimatter Beam Generation and Manipulation proton, antiproton, experiment, simulation 2118
 
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
 
  Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska Curie grant agreement No 721559.
The Accelerators Validating Antimatter physics (AVA) project has enabled an interdisciplinary and cross-sector R&D program on low energy antimatter research. The network comprises 13 universities, 9 national and inter-national research centers and 13 partners from industry. Between 2016 and 2021, AVA has successfully trained 16 early-stage researchers that were based at universities, research centers and companies across Europe where they carried out cutting edge research into low energy antimat-ter physics and related technologies. This contribution presents several research highlights that originated within or on the basis of AVA: Results from studies into carbon nano-tubes as field emitters for cold electron beams with supe-rior beam quality, the design of a low energy negative ion injection beamline for experiments with antiprotonic atoms, and studies into realistic simulations of antiproton deceleration in foil degraders.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK029  
About • Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK035 Layout of the 12 O’clock Collimation Straight Section for the EIC Hadron Storage Ring hadron, dipole, operation, storage-ring 2142
 
  • G. Robert-Demolaize, J.S. Berg, K.A. Drees, D. Holmes, H. Lovelace III, S. Peggs, M. Valette
    BNL, Upton, New York, USA
  • B. Bhandari
    Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
 
  Funding: Work supported by the US Department of Energy under contract No. DE-SC0012704.
The design of the Electron-Ion Collider (EIC) Hadron Storage Ring (HSR) calls for using parts of both of the Relativistic Heavy Ion Collider (RHIC) Blue and Yellow beamlines. With the HSR having to circulate low (41 GeV) and high (100+ GeV) energy hadron beams while matching the time of flight in the Electron Storage Ring (ESR), it becomes necessary for the ring lattice to switch from an outer arc to an inner arc in order to accommodate for the change in circumference. To do so, a switchyard is planned for installation in the HSR straight section at 12 o’clock with the other switchyard being placed in the straight section immediately downstream, 10 o’clock. The 12 o’clock straight section is simultaneously dedicated to the EIC 2-stage collimation system. The following reviews the layout constraints in the12 o’clock straight section that come with installing such a switchyard, along with the implications on the linear optics for that straight section at all HSR rigidities. The space allocation, twiss parameters and the mechanical requirements of the HSR betatron collimators that will be installed in this section are also discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK035  
About • Received ※ 07 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 27 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK036 Progress on Electron Beam Optimization for FLASH Radiotherapy Experiment at Chiang Mai University simulation, experiment, radiation, linac 2146
 
  • K. Kongmali, P. Apiwattanakul, S. Rimjaem, J. Saisut, C. Thongbai
    Chiang Mai University, Chiang Mai, Thailand
  • P. Apiwattanakul, N. Kangrang
    Chiang Mai University, PBP Research Facility, Chiang Mai, Thailand
  • M. Jitvisate
    Suranaree University of Technology, Nakhon Ratchasima, Thailand
  • P. Lithanatudom
    IST, Chiang Mai, Thailand
 
  At present, one of diseases that kills many people worldwide is cancer. The FLASH radiotherapy (RT) is a promising cancer treatment under study. It involves the fast delivery of RT at much higher dose rates than those currently used in clinical practice. The very short time of exposure leads to the destruction of the cancer cells, while the nearby normal cells are less damaged as compared with conventional RT. This work focuses on study of FLASH-RT experiment using electron beams produced from the accelerator system at the PBP-CMU Electron Linac Laboratory. The structure and properties of our electron pulses with microbunches in picosecond time scale and macropulses in microsecond time scale match well to FLASH-RT requirement. To optimize the condition for experiment, the electron beam simulations are performed by varying energy, charge and bunch length. The 25 MeV electrons energy before hitting the window for 50 and 100 pC bunch length have a bunch length of 1.16 and 1.97 ps. The transverse rms beam sizes of 50 pC and 100 pC bunch charges have the differences between ASTRA and GEANT4 from 7.90 % to 34.0 %. The optimized electron beam properties from this study will be used as the guideline for further simulation and experiment preparation.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK036  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 20 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK037 Radiation of a Particle Moving Along a Helical Trajectory in a Resistive-Wall Cylindrical Waveguide GUI, radiation, undulator, laser 2150
 
  • M. Ivanyan, A. Grigoryan, B. Grigoryan, B.K. Sargsyan
    CANDLE SRI, Yerevan, Armenia
  • K. Flöttmann, F. Lemery
    DESY, Hamburg, Germany
  • A. Grigoryan
    YSU, Yerevan, Armenia
 
  Funding: The work was supported by the Science Committee of RA, in the frames of the research project 21T-1C239
The radiation field of a particle moving on a helical trajectory in a cylindrical waveguide with resistive walls is calculated. The deformation of the energy spectrum of radiation, as a result of the finite conductivity of the walls, is investigated.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK037  
About • Received ※ 31 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK043 Matching Studies Between the CERN PSB and PS Using Turn-by-Turn Beam Profile Acquisitions with a Residual Beam Gas Ionisation Monitor injection, emittance, proton, operation 2161
 
  • M.A. Fraser, M.R. Coly, A. Guerrero, A. Huschauer, S. Jensen, S. Levasseur, F. Roncarolo, A. Rossi, H.S. Sandberg, J.W. Storey
    CERN, Meyrin, Switzerland
 
  In the framework of the LHC Injectors Upgrade project, the Beam Gas Ionisation (BGI) profile monitors installed in the Proton Synchrotron (PS) were fitted with a gas injection system capable of boosting the signal rate high enough to capture single turn acquisitions immediately after injection. This contribution reports on the studies carried out during the beam commissioning of the BGI system in a turn-by-turn matching monitor mode for its eventual implementation in an optimisation framework to preserve emittance during transfer between the PS Booster and PS. The BGI commissioning included a benchmarking with data from a wire-grid secondary emission monitor inserted into the circulating beam.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK043  
About • Received ※ 02 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 30 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK057 Towards Direct Detection of the Shape of CSR Pulses with Fast THz Detectors detector, radiation, synchrotron, synchrotron-radiation 2190
 
  • J.L. Steinmann, M. Brosi, E. Bründermann, A. Mochihashi, A.-S. Müller, P. Schreiber
    KIT, Karlsruhe, Germany
 
  Funding: We acknowledge in part support by the Helmholtz President’s strategic fund IVF "Plasma accelerators". This work is funded in part by the BMBF contract number: 05K19VKD.
Coherent synchrotron radiation (CSR) is emitted when the emitting structure is equal to or smaller than the observed wavelength. Consequently, these pulses are very short and most detectors respond with their impulse response, regardless of the pulse length and shape. Here we present single-shot measurements performed at the Karlsruhe Research Accelerator (KARA) using a fast real-time oscilloscope and Schottky barrier detectors sensitive in the sub-THz range. The time response of this setup to CSR pulses emitted by electron bunches during the microbunching instability is shown to be sensitive to the shape of the electron bunch. Our results show how, in the future, the shape of electron bunches can be directly measured using a straightforward setup.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK057  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 09 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK060 Prospects of Ultrafast Electron Diffraction Experiments at Sealab experiment, SRF, cavity, gun 2201
 
  • B. Alberdi-Esuain, J.-G. Hwang, T. Kamps, A. Neumann, J. Völker
    HZB, Berlin, Germany
  • T. Kamps
    HU Berlin, Berlin, Germany
 
  Ultrafast Electron Diffraction (UED) is a pump-probe experimental technique that aims to image the structural changes that happen in a target structure due to photo-excitation. Development of MeV UED capabilities is one of the main objectives at Sealab, a superconducting RF accelerator facility being commissioned in Helmholtz-Zentrum Berlin. In order to perform UED experiments, the optimization of temporal resolution is of the utmost importance. The composition of the SRF Photoinjector, currently the main beam-line in Sealab, offers superb flexibility to manipulate the longitudinal phase-space of the electron bunch. At the same time, the CW operation of the accelerator provides an enhanced beam stability compared to warm guns, together with MHz repetition rates. This work aims to show the capacity of the SRF Photoinjector in Sealab to reach the required temporal resolution and explain the development and current status of the necessary tools to perform UED experiments at the facility.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK060  
About • Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 03 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK061 Lattice Design of the UVSORIV Storage Ring emittance, lattice, storage-ring, dynamic-aperture 2205
 
  • E. Salehi, M. Fujimoto, M. Katoh, Y. Taira
    UVSOR, Okazaki, Japan
  • L. Guo
    Nagoya University, Nagoya, Japan
  • M. Katoh
    HSRC, Higashi-Hiroshima, Japan
 
  We are designing a storage ring lattice for the future plan of UVSOR. As a candidate, we have designed a storage ring of 1 GeV electron energy, which is higher than the present value, 750 MeV. The magnetic lattice is based on a compact double bend achromat cell, which consists of two bending magnets and four focusing magnets, all of which are of combined function. The circumference is around 82.5 m. The emittance is around 4 nm in the achromatic condition, which becomes lower in the non-achromatic condition. The lattice of 6-fold symmetry has six straight sections of 4 m long and six of 1.5 m long. Undulators can radiate nearly diffraction-limited light in VUV. If we install high field multipole wiggler at the short straight sections, they can provide high flux tender X-rays. We are expecting the usage of a laser-based accelerator as the injector, which might be developed in the next decade. As an alternative plan, we have designed a traditional injector, which consists of a linear accelerator and a booster synchrotron and can be constructed inside of the storage ring.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK061  
About • Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK064 Generating Sub-Femtosecond Electron Beams at Plasma Wakefield Accelerators plasma, emittance, simulation, wakefield 2217
 
  • R. Robles, C. Emma, R.M. Hessami, K. Larsen, A. Marinelli
    SLAC, Menlo Park, California, USA
 
  Funding: This work was supported by US Department of Energy Contracts No. DE-AC02-76SF00515 and by the DOE, Laboratory Directed Research and Development program at SLAC, under contract DE-AC02-76SF00515.
The Plasma-driven Attosecond X-ray source (PAX) project at FACET-II aims to produce attosecond EUV/soft x-ray pulses with milijoule-scale pulse energy via nearly coherent emission from pre-bunched electron beams. In the baseline approach*, a beam is generated using the density downramp injection scheme with a percent-per-micron chirp and 1e-4 scale slice energy spread. Subsequent compression yields a current spike of just 100 as duration which can emit 10 nm light nearly coherently due to its strong pre-bunching. In this work, we report simulation studies of a scheme to generate similarly short beams without relying on plasma injection. Instead, we utilize a high-charge beam generated at an RF photocathode, with its tail acting as the witness bunch for the wake. The witness develops a percent-per-micron chirp in the plasma which is then compressible downstream. The final bunch length demonstrated here is as short as 100 nm, and is limited primarily by emittance effects. The configurations studied in this work are available for experimental testing at existing PWFA facilities such as FACET-II.
*APL Photonics 6, 076107 (2021)
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK064  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOTK065 Revisiting Intrabeam Scattering for Laminar Beams space-charge, scattering, simulation, emittance 2221
 
  • R. Robles, Z. Huang, A. Marinelli
    SLAC, Menlo Park, California, USA
 
  Funding: This work was supported by US Department of Energy Contracts No. DE-AC02-76SF00515
Intrabeam scattering (IBS) is becoming an increasingly important effect in the design of high-brightness linear electron accelerators due to the ever-increasing transverse brightness of beams produced from radiofrequency photoinjectors. The existing theory describing the energy spread growth rate due to IBS was derived in the context of circular machines where the beam particles are frequently and randomly colliding, and therefore should only be applied to non-laminar, emittance dominated flow. This is not the case in the injector portion of a linear accelerator, where the beam is space-charge dominated and the flow is laminar. The different nature of the microscopic motion in the two cases demands a reevaluation of the applicability of IBS theory to the photoinjector. In this work, we present a simple analytic model for energy spread growth during perfectly laminar flow and show that it matches well to point-to-point multiparticle simulations. In this way we demonstrate that stochastic energy spread growth in laminar beams is more attributable to the initial random placement of the particles in the bunch rather than the traditional temperature rearrangement mechanism of IBS.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK065  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS015 Basic Relations of Laser-Plasma Interaction in the 3D Relativistic, Non-Linear Regime laser, plasma, wakefield, acceleration 2265
 
  • D.F.G. Minenna, E. Bargel, L. Batista, P.A.P. Nghiem
    CEA-IRFU, Gif-sur-Yvette, France
 
  In the approximation where the plasma is considered as a fluid, basic relations are derived to describe the plasma wave driven by an ultra-intense laser pulse. A set of partial differential equations is obtained. It is then numerically solved to calculate the resulting 3D electric field structure that can be used as accelerating cavities for electrons. The laser strength parameter is varied to investigate regimes from weakly nonlinear up to total cavitation where all the initial electrons of the plasma are expelled.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS015  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS022 Detailed Analysis of Transverse Emittance of the FLUTE Electron Bunch emittance, laser, simulation, quadrupole 2289
 
  • T. Schmelzer, E. Bründermann, A.-S. Müller, M.J. Nasse, R. Ruprecht, J. Schäfer, M. Schuh, N.J. Smale, P. Wesolowski
    KIT, Karlsruhe, Germany
 
  The compact and versatile linear accelerator-based test facility FLUTE (Ferninfrarot Linac- Und Test-Experiment) is operated at KIT. Its primary goal is to serve as a platform for a variety of accelerator R\&D studies like the generation of strong ultra-short terahertz pulses. The amplitude of the generated coherent THz pulses is proportional to the square number of particles in the bunch. With the transverse emittance a measure for the transverse particle density can be determined. It is therefore a vital parameter in the optimization for operation. In a systematic study, the transverse emittance of the electron beam was measured in the FLUTE injector. A detailed analysis considers different influences such as the bunch charge and compares this with particle tracking simulations carried out with ASTRA. In this contribution, the key findings of this analysis are discussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS022  
About • Received ※ 08 June 2022 — Revised ※ 23 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS023 Optimization Studies of Simulated THz Radiation at FLUTE radiation, linac, simulation, synchrotron 2292
 
  • C. Xu, E. Bründermann, A.-S. Müller, A. Santamaria Garcia, J. Schäfer, M. Schwarz
    KIT, Karlsruhe, Germany
 
  Funding: Supported by the Helmholtz Association (Autonomous Accelerator, ZT-I-PF-5-6) and the DFG-funded Doctoral School "Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology".
The linac-based test facility FLUTE (Ferninfrarot Linac Und Test Experiment) at KIT will be used to study novel accelerator technology and provide intense THz pulses. In this paper, we present start-to-end simulation studies of FLUTE with different bunch charges. We employ a parallel Bayesian optimization algorithm for different bunch charges of FLUTE to find optimized accelerator settings for the generation of intense THz radiation.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS023  
About • Received ※ 20 May 2022 — Accepted ※ 21 June 2022 — Issue date ※ 10 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS025 Injector Design Towards ERL-Based EUV-FEL for Lithography emittance, cavity, FEL, solenoid 2299
 
  • O.A. Tanaka, T. Miyajima, N. Nakamura, T. Tanikawa
    KEK, Ibaraki, Japan
 
  A high-power EUV light source using ERL-based FEL can supply multiple semiconductor exposure de-vices. There are some requirements in the whole and its injector, in particular, and their examination and necessary development are being carried out. The requirement for the injector was to generate high bunch charge beams at a high-repetition rate. In this regard, a space charge effect should be treated carefully in the design of the injector. For FEL operation, not only short bunch length and small transverse emittance but also small longitudinal emittance are required. By using a multi-objective genetic algorithm, we are minimizing them at the exit of the injector to investigate the injector performance and its effect on the FEL generation. In this study, we describe the injector optimization strategies and possible options suited for the ERL-based EUV-FEL.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS025  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS028 Electron Beam Shaping Techniques Using Optical Stochastic Cooling synchrotron, undulator, controls, radiation 2303
 
  • A.J. Dick, P. Piot
    Northern Illinois University, DeKalb, Illinois, USA
  • P. Piot
    ANL, Lemont, Illinois, USA
 
  Optical Stochastic Cooling (OSC) has demonstrated its ability to reduce the three-dimensional phase-space emittance of an electron beam by applying a small corrective kick to the beam each turn. By modifying the shape and timing of these kicks we can produce specific longitudinal beam distributions. Two methods are introduced; single-pulse modulation, where the longitudinal profile of the OSC pulse is amplified by some function, as well as multiple-turn modulation, where the overall strength or phase is varied depending on the synchrotron oscillation phase. The shaping techniques are demonstrated using a model of OSC developed in the ELEGANT particle-tracking code program.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS028  
About • Received ※ 13 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 21 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS032 Simulations of Coherent Electron Cooling with Orbit Deviation simulation, plasma, kicker, hadron 2319
 
  • J. Ma, V. Litvinenko, G. Wang
    BNL, Upton, New York, USA
  • V. Litvinenko
    Stony Brook University, Stony Brook, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
Coherent electron cooling (CeC) is a novel technique for rapidly cooling high-energy, high-intensity hadron beam. Plasma cascade amplifier (PCA) has been proposed for the CeC experiment in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). Cooling performance of PCA based CeC has been predicted in 3D start-to-end CeC simulations using code SPACE. The dependence of the PCA gain and the cooling rate on the electron beam’s orbit deviation has been explored in the simulation studies.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS032  
About • Received ※ 16 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS037 Microbunching Studies for the FLASH2020+ Upgrade Using a Semi-Lagrangian Vlasov Solver bunching, simulation, laser, FEL 2334
 
  • Ph. Amstutz, M. Vogt
    DESY, Hamburg, Germany
 
  Precise understanding of the microbunching instability is mandatory for the successful implementation of a compression strategy for advanced FEL operation modes such as the EEHG seeding scheme, which a key ingredient of the FLASH2020+ upgrade project. Simulating these effects using particle-tracking codes can be quite computationally intensive as an increasingly large number of particles is needed to adequately capture the dynamics occurring at small length scales and reduce artifacts from numerical shot-noise. For design studies as well as dedicated analysis of the microbunching instability semi-Lagrangian codes can have desirable advantages over particle-tracking codes, in particular due to their inherently reduced noise levels. However, rectangular high-resolution grids easily become computationally expensive. To this end we developed SelaV1D, a one dimensional semi-Lagrangian Vlasov solver, which employs tree-based domain decomposition to allow for the simulation of entire exotic phase-space densities as they occur at FELs. In this contribution we present results of microbunching studies conducted for the FLASH2020+ upgrade using SelaV1D.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS037  
About • Received ※ 06 June 2022 — Revised ※ 29 June 2022 — Accepted ※ 01 July 2022 — Issue date ※ 09 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS039 Analysis of Xcos Simulation Model for Intensity at Third and Fifth Harmonics Undulator Radiation undulator, radiation, simulation, FEL 2338
 
  • H. Jeevakhan
    NITTTR, Bhopal, India
  • K. Kushwaha, M. Syed
    RGPV, Bhopal, India
  • G. Mishra
    Devi Ahilya University, Indore, India
 
  Xcos simulation model is analysed for the intensity of planar undulator radiation at the third and fifth harmonics. The Xcos model is designed by using the numerical approach. The results obtained from the simulation model are compared with the analytical method. The model can also be utilized for observing the effect of energy spread on radiation by numerical approach. An algorithm for analysing the effect of energy spread is also presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS039  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS042 The HOMEN Model: An Estimator of High Order Modes Evolution in an Energy Recovery Linac cavity, HOM, acceleration, linac 2342
 
  • S. Samsam, A. Bacci, V. Petrillo, M. Rossetti Conti, A.R. Rossi, M. Ruijter, L. Serafini
    INFN-Milano, Milano, Italy
  • A. Bosotti, R. Paparella, D. Sertore
    INFN/LASA, Segrate (MI), Italy
  • M.R. Masullo, A. Passarelli
    INFN-Napoli, Napoli, Italy
  • M. Opromolla
    Università degli Studi di Milano, Milano, Italy
 
  Energy recovery linacs represent the new frontier of energy sustainability in the field of particle accelerators while providing remarkable performance in terms of high average current and average brightness. Operating superconducting radio-frequency cavities in continuous wave makes high repetition rates (GHz-class) affordable and allows the construction of light sources such as FEL or Compton based characterized by high flux. \ This study originates in the context of the design study of BriXSinO, an ERL based on the two-pass two-way scheme à la Maury Tigner in which the cavities are traveled by the beam in both directions, the first time in the accelerating phase and the second time in the decelerating phase. HOMEN was conceived as a model to simulate the evolution of high order modes on long time scales in high Q cavities of machines of this kind and monitor their effects on the beam.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS042  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS043 UFO, a GPU Code Tailored Toward MBA Lattice Optimization GPU, lattice, simulation, optics 2346
 
  • M. Carlà, M. Canals
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  The complexity of multi-bend achromatic optics is such that computational tools performance has become a dominant factor in the design process a last generation synchrotron light source. To relieve the problem a new code (UFO) tailored toward performance was developed to assist the design of the ALBA-II optics. Two main strategies contribute to the performance of UFO: the execution flow follows a data parallel paradigm, well suited for GPU execution; the use of a just-in-time compiler allows to simplify the computation whenever the lattice allows for it. At the core of UFO lies a parallel tracking routine structured for parallel simulation of optics which differs in some parameters, such as magnet strength or alignment, but retains the same element order, reflecting the scenario found in optimization processes, or when dealing with magnetic or alignment errors. Such an approach allows to take advantage of GPUs which yield the best performance when running thousands of parallel threads. Moreover UFO is not limited to tracking. A few modules that rely on the same tracking routine allow for the fast computation of dynamic and momentum aperture, closed orbit and linear optics.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS043  
About • Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 19 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS051 Spin Matching for the EIC’s Electrons polarization, emittance, lattice, storage-ring 2369
 
  • M.G. Signorelli
    Cornell University, Ithaca, New York, USA
  • J.A. Crittenden, G.H. Hoffstaetter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • J. Kewisch
    BNL, Upton, New York, USA
 
  The Electron-Ion Collider (EIC) at Brookhaven National Laboratory will provide spin-polarized collisions of electron and protons or light ion beams. In order to maximize the electron polarization and require less frequent beam re-injections to restore the polarization level, the stochastic depolarizing effects of synchrotron radiation must be minimized via spin matching. In this study, Bmad was used to perform first order spin matching in the Electron Storage Ring (ESR) of the EIC. Spin matches were obtained for the rotator systems and for a vertical chicane, inserted as a vertical emittance creator. Monte Carlo spin tracking with radiation was then performed to analyze the effects of the spin matching on the polarization.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS051  
About • Received ※ 31 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS052 Impacts of an ATS Lattice on EIC Dynamic Aperture sextupole, lattice, optics, collider 2373
 
  • J.E. Unger, J.A. Crittenden, G.H. Hoffstaetter
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • D. Marx
    BNL, Upton, New York, USA
 
  The Electron-Ion Collider (EIC) project at Brookhaven National Laboratory has explored strategies for increasing the energy aperture of the Electron Storage Ring (ESR) to meet the goal of 1\% for the 90 degree lattice at 18 GeV. Current strategies use a four sextupole family per arc correction scheme to increase the energy aperture and to keep the transverse aperture sufficiently large as well. A scheme called Achromatic Telescopic Squeezing (ATS), first introduced for the Large Hadron Collider, introduces a beta-beat into select arcs, allowing dynamic aperture optimizations with different sextupole strengths. The ATS scheme’s mix of some higher beta-function and some lower sextupole strengths in the arcs has the potential to increase the energy aperture. Basic chromatic corrections and numeric optimizations were used to compare the ATS optics to a non-ATS scheme. In all cases, the ATS scheme performed similarly or better than the more common schemes. However, this increase in energy aperture from the ATS optics also has negative effects, such as an increase in emittance which poses complications for the current ESR design.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS052  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS056 Spin Matching and Monte-Carlo Simulation of Radiative Spin Depolarization in e+e Storage Rings with Bmad polarization, resonance, storage-ring, lattice 2383
 
  • O. Beznosov, J.A. Ellison, K.A. Heinemann
    UNM-MATH, Albuquerque, New Mexico, USA
  • D.P. Barber
    DESY, Hamburg, Germany
  • J.A. Crittenden, G.H. Hoffstaetter, D. Sagan
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
 
  Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics, under Award Numbers DE-SC0018008 and DE-SC0018370.
The Bmad/Tao software toolkit has been extended to estimate the rate of radiative spin depolarization in e+/e storage rings. First estimates are made using the SLIM algorithm of linearized spin-orbit motion. The extension implements the effects on s-o motion of stochastic photon emission using a Monte-Carlo tracking algorithm. Spins are tracked in 3-D along particle trajectories with the aid of Taylor expansions of quaternions provided by PTC*. The efficiency of long-term tracking is guarantied by the use of a sectioning technique that was exploited in previous-generation software**. Sectioning is the construction of the deterministic s-o maps for sections between the dipoles during the initialization phase. Maps can be reused during the tracking. In a simulation for a realistic storage ring, the computational cost of initial map construction is amortized by the multi-turn tracking computational cost. The use of 1st-order terms in the quaternion expansions to construct the s-o coupling matrices in the matrices of the SLIM algorithm. These matrices are then available for an extension of the optimization facilities in Bmad to minimize depolarizing effects by spin matching.
*SLICKTRACK and SITROS
** Polymorphic Tracking Code by Etienne Forest
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS056  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPOMS057 Simulation Studies and Machine Learning Applications at the Coherent electron Cooling experiment at RHIC LEBT, emittance, quadrupole, solenoid 2387
 
  • W. Lin, J.A. Crittenden, G.H. Hoffstaetter, M.A. Sampson
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • Y.C. Jing
    BNL, Upton, New York, USA
  • K. Shih
    SBU, Stony Brook, New York, USA
 
  Funding: Work supported by the U.S. National Science Foundation under Award PHY-1549132, and by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Coherent electron cooling is a novel cooling technique which cools high-energy hadron beams rapidly by amplifying the modulation induced by hadrons in electron bunches. The Coherent electron cooling (CeC) experiment at Brookhaven National Laboratory (BNL) is a proof-of-principle test facility to demonstrate this technique. To achieve efficient cooling performance, electron beams generated in the CeC need to meet strict quality standards. In this work, we first present sensitivity studies of the low energy beam transport (LEBT) section, in preparation for building a surrogate model of the LEBT line in the future. We also present preliminary test results of a machine learning (ML) algorithm developed to improve the efficiency of slice-emittance measurements in the CeC diagnostic line.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS057  
About • Received ※ 06 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 15 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THOXGD2 Electron Cooling Experiment for Proton Beams with Intense Space-Charge in IOTA space-charge, proton, simulation, emittance 2395
 
  • N. Banerjee, J.A. Brandt
    Enrico Fermi Institute, University of Chicago, Chicago, Illinois, USA
  • M.K. Bossard, Y.K. Kim
    University of Chicago, Chicago, Illinois, USA
  • B.L. Cathey, S. Nagaitsev, G. Stancari
    Fermilab, Batavia, Illinois, USA
 
  Funding: Fermi Research Alliance, LLC under Contract No.~DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics and also the University of Chicago.
Electron cooling as a method of creating intense ion beams has a practical upper limit when it comes to the peak phase space density of ion beams which can be achieved in practice. We describe a new experiment to study electron cooling of 2.5 MeV protons at the intensity limit using the Integrable Optics Test Accelerator (IOTA), which is a storage ring dedicated to beam physics research at Fermilab. This system will enable the study of magnetized electron cooling of a proton beam with transverse incoherent tune shifts approaching -0.5 due to the presence of intense space-charge forces. We present an overview of the hardware design, simulations and specific experiments planned for this project.
 
slides icon Slides THOXGD2 [2.775 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THOXGD2  
About • Received ※ 13 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THIXSP1 A New Compact 3 GeV Light Source in Japan vacuum, cavity, emittance, quadrupole 2402
 
  • N. Nishimori
    QST, Tokai, Japan
 
  A new 3 GeV light source with a circumference of 350 m and an MBA lattice has been officially funded and is being constructed in north-eastern Japan. Aiming at stable and high-performance operations with an emittance of about 1 nm rad, various design and R&D activities are being performed: the four bend achromatic lattice using BQ combined function magnets; the compact RF system using a TM020 mode and in-cavity compact HOM absorbers; the in-vacuum off-axis injection scheme enabling stored beam oscillation-free injections with a small injection beam amplitude; the injector linac composed of a thermionic E-gun and C-band accelerators with a capability of extension to feed a future SX-FEL driver, and so on. The installation of accelerator components is ongoing. The talk will include the overall design of the light source, R&D results, and the latest construction status.  
slides icon Slides THIXSP1 [15.084 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THIXSP1  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 25 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THOXSP2 Brixsino High-Flux Dual X-Ray and THz Radiation Source Based on Energy Recovery Linacs cavity, laser, radiation, linac 2407
 
  • I. Drebot, F. Canella, S. Cialdi, M. Giammarchi, D. Giannotti, S. Latorre, C. Meroni, M. Rossetti Conti, A.R. Rossi, M. Ruijter, S. Samsam, L. Serafini, V. Torri
    INFN-Milano, Milano, Italy
  • M.P. Abbracchio, S. Altilia, B. Paroli, A. Vanzulli
    Universita’ degli Studi di Milano, Milano, Italy
  • A. Andreone, G.P. Papari
    Naples University Federico II, Napoli, Italy
  • A. Bacci, M. Bertucci, A. Bosotti, F. Broggi, D. Giove, P. Michelato, L. Monaco, R. Paparella, L. Rossi, D. Sertore, M. Statera
    INFN/LASA, Segrate (MI), Italy
  • R. Calandrino, A. Delvecchio
    HSP, Milan, Italy
  • S. Capra, D. Cipriani, C. Lenardi, M. Opromolla, E. Suerra, A. Torresin
    Università degli Studi di Milano, Milano, Italy
  • P. Cardarelli, G. Paternò, A. Taibi
    INFN-Ferrara, Ferrara, Italy
  • M. Citterio
    Universita’ degli Studi di Milano e INFN, Milano, Italy
  • A. Esposito
    LNF-INFN, Frascati, Italy
  • R. Ferragut, G. Galzerano
    POLIMI, Milano, Italy
  • C. Koral, M.R. Masullo, A. Passarelli
    INFN-Napoli, Napoli, Italy
  • Z. Mazaheri, G. Mettivier, P. Russo
    UniNa, Napoli, Italy
  • C. Pagani
    Università degli Studi di Milano & INFN, Segrate, Italy
  • P. Paparo
    CNR-ISASI, Pozzuoi, Italy
  • V. Petrillo, F. Prelz, M. Sorbi
    Universita’ degli Studi di Milano & INFN, Milano, Italy
  • B. Piccirillo, A. Rubano
    Naples University Federico II and INFN, Napoli, Italy
  • E. Puppin
    Politecnico/Milano, Milano, Italy
 
  We present the conceptual design of a compact light source named BriXSinO. BriXSinO was born as demonstrator of the Marix project, but it is also a dual high flux radiation source Inverse Compton Source (ICS) of X-ray and Free-Electron Laser of THz spectral range radiation conceived for medical applications and general applied research. The accelerator is a push-pull CW-SC Energy Recovery Linac (ERL) based on superconducting cavities technology and allows to sustain MW-class beam power with almost just one hundred kW active power dissipation/consumption. ICS line produces 33 keV monochromatic X-Rays via Compton scattering of the electron beam with a laser system in Fabry-Pérot cavity at a repetition rate of 100 MHz. The THz FEL oscillator is based on an undulator imbedded in optical cavity and generates THz wavelengths from 15 to 50 micron.  
slides icon Slides THOXSP2 [19.118 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THOXSP2  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THOXSP3 Path to High Repetition Rate Seeding: Combining High Gain Harmonic Generation with an Optical Klystron FEL, laser, simulation, klystron 2411
 
  • G. Paraskaki, E. Ferrari, L. Schaper, E. Schneidmiller
    DESY, Hamburg, Germany
  • E. Allaria
    Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
  • W. Hillert
    University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
 
  External seeding in combination with harmonic generation has become a hot topic in the field of high gain free-electron lasers (FELs) since it allows delivery of superior FEL radiation characterized by, for example, full coherence and unprecedented shot-to-shot stability. At low repetition rate machines operating at few 10 Hz, novel experiments have been realized already, however, at superconducting machines, current laser technology does not support exploiting the full repetition rate available. One way to overcome this problem is to reduce the requirements in seed laser power: here, an optical klystron based high gain harmonic generation (HGHG) setup is proposed to reduce the laser peak power requirements by orders of magnitude, enabling operation at drastically increased repetition rates. We report simulation results based on the seeded beamline concept of the FLASH2020+ project. Among other topics, the effect of a linear electron beam energy chirp on this setup will be discussed.  
slides icon Slides THOXSP3 [1.502 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THOXSP3  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THIYGD1 White Rabbit Based Beam-Synchronous Timing Systems for SHINE timing, network, FEL, FPGA 2415
 
  • Y.B. Yan, G.H. Chen, Q.W. Xiao, P.X. Yu
    SSRF, Shanghai, People’s Republic of China
  • G.H. Gong
    Tsinghua University, Beijing, People’s Republic of China
  • J.L. Gu, Z.Y. Jiang, L. Zhao
    USTC, Hefei, Anhui, People’s Republic of China
  • Y.M. Ye
    TUB, Beijing, People’s Republic of China
 
  Shanghai HIgh repetition rate XFEL aNd Extreme light facility (SHINE) is under construction. SHINE requires precise distribution and synchronization of the 1.003086 MHz timing signals over a long distance of about 3.1 km. Two prototype systems were developed, both containing three functions: beam-synchronous trigger signal distribution, random-event trigger signal distribution and data exchange between nodes. The frequency of the beam-synchronous trigger signal can be divided according to the accelerator operation mode. Each output pulse can be configured for different fill modes. A prototype system was designed based on a customized clock frequency point (64.197530 MHz). Another prototype system was designed based on the standard White Rabbit protocol. The DDS (Direct Digital Synthesis) and D flip-flops (DFFs) are adopted for RF signal transfer and pulse configuration. The details of the timing system design, laboratory test results will be reported in this paper.  
slides icon Slides THIYGD1 [5.582 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THIYGD1  
About • Received ※ 29 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THOYGD1 Experimental Verification of Several Theoretical Models for ChDR Description radiation, experiment, diagnostics, beam-diagnostic 2420
 
  • K. Łasocha
    Jagiellonian University, Kraków, Poland
  • C. Davut
    The University of Manchester, Manchester, United Kingdom
  • P. Karataev
    Royal Holloway, University of London, Surrey, United Kingdom
  • T. Lefèvre, S. Mazzoni, E. Senes
    CERN, Meyrin, Switzerland
  • C. Pakuza
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
  • A. Schloegelhofer
    TU Vienna, Wien, Austria
 
  In recent years the potential of using Cherenkov Diffraction Radiation (ChDR) as a tool for non-invasive beam diagnostics has been thoroughly investigated. Although several theoretical models of ChDR have been developed, differences in their assumptions result in inconsistent predictions. The experimental verification is therefore needed in order to fully understand ranges of validity of available models. In this contribution we present a detailed theoretical study of the radiation yield as a function of the beam-radiator distance. Following identification of beam parameters and frequency range for which differences between the model predictions are most prominent, we compare theoretical estimates with the results of a dedicated experiment.  
slides icon Slides THOYGD1 [0.838 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THOYGD1  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 19 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST003 Collective Effects Estimates for the Damping Ring Design of the FCC-ee emittance, impedance, damping, positron 2435
 
  • O. Etisken
    Ankara University, Faculty of Sciences, Ankara, Turkey
  • F. Antoniou, F. Zimmermann
    CERN, Meyrin, Switzerland
  • A. De Santis
    INFN/LNF, Frascati, Italy
  • C. Milardi
    LNF-INFN, Frascati, Italy
 
  The current injector complex design of the FCC-e+e project consists of e+/e linacs, which accelerate the beams up to 6 GeV, a damping ring at 1.54 GeV, a pre-booster ring, accelerating the beam up to 16 GeV and a booster synchrotron ring integrated in the collider tunnel accelerating the beams up to the collision energies. The purpose of the damping ring is to accept the 1.54 GeV beam coming from the linac-1, damp the positron/electron beams and provide the required beam characteristics for the injection into the linac-2. In this presentation the current damping ring design is introduced and analytical calculations on various collective effect such as space charge, intra-beam scattering, longitudinal micro-wave instability, transverse mode coupling instability, ion effects, electron cloud and coherent synchrotron radiation, are presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST003  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST004 EIC’s Rapid Cycling Synchrotron Spin Tracking Update polarization, emittance, lattice, resonance 2439
 
  • V.H. Ranjbar, H. Lovelace III, F. Méot
    BNL, Upton, New York, USA
  • F. Lin
    ORNL RAD, Oak Ridge, Tennessee, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The Electron Ion Collider (EIC) to be built will collide polarized electrons and ions up to 140 GeV center of mass with a time averaged polarization of 70% and luminosity up to 1034 cm-2 s-1. The EIC’s Rapid Cycling Synchrotron (RCS) will accelerate 2 polarized electrons bunches from 400 MeV to energies of 5, 10 and 18 GeV and inject them into the EIC’s Electron Storage Ring. The design of the RCS has progressed to accommodate a larger magnet free section for the detectors and to meet the space requirements of the RHIC tunnel. We present progress on full 6D spin tracking studies of the RCS with the updated lattice using the Zgoubi code to include magnet misalignments, field errors and corrections as well as radiative effects.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST004  
About • Received ※ 07 June 2022 — Revised ※ 22 June 2022 — Accepted ※ 24 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST006 Simulations of the Suitability of a DC Electron Photogun and S-Band Accelerating Structure as Input to an X-Band Linac gun, simulation, emittance, acceleration 2445
 
  • S.D. Williams, R.P. Rassool, S.L. Sheehy, G. Taylor, M. Volpi
    The University of Melbourne, Melbourne, Victoria, Australia
  • R. Auchettl, R.T. Dowd
    AS - ANSTO, Clayton, Australia
 
  Work has been underway for some time to design a compact electron beamline utilising X-band linear accelerating structures in the new Melbourne X-band Laboratory for Accelerators and Beams (X-LAB). The original design utilised an S-band RF photogun as an input to a pair of high gradient X-band linear accelerating structures, but we have been motivated to investigate an alternative starting section to allow for initial testing. This will utilise a DC photogun and S-band accelerating structure similar to those used at the Australian Synchrotron. Simulation results incorporating space charge of a beamline composed of a DC photogun, S-band accelerating structures, and two high gradient X-band structures will be presented. These simulation results will be optimised for minimum emittance at the end of the beamline.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST006  
About • Received ※ 20 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST007 Slow-Control Loop to Stabilize the RF Power of the FLUTE Electron Gun controls, cavity, gun, LLRF 2449
 
  • M.-D. Noll, A. Böhm, J. Jelonek, I. Križnar, O. Manzhura, A.-S. Müller, R. Ruprecht, M. Schuh, N.J. Smale
    KIT, Karlsruhe, Germany
 
  The linear accelerator FLUTE (Far Infrared Linac and Test Experiment) at KIT serves as a test facility for accelerator research and for the generation of ultra-intense coherent THz radiation. To achieve stable THz photon energy and optimal beam trajectory, the energy of the electrons emitted from the RF photo-injector must be stable. The accelerating voltage of the RF cavity has been shown to be a significant influencing factor. Here, we report on the development of a slow closed-loop feedback system to stabilize the RF power and thus the accelerating voltage in the RF photo-injector cavity. With this closed-loop feedback system the relative standard deviation of the RF power in the cavity can be improved by 8.5 %.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST007  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST008 Status of the FLUTE RF System Upgrade linac, GUI, solenoid, storage-ring 2452
 
  • A. Malygin, O. Manzhura, A.-S. Müller, R. Ruprecht, M. Schuh, N.J. Smale
    KIT, Karlsruhe, Germany
 
  FLUTE (Ferninfrarot Linac- Und Test-Experiment) is a compact versatile linac-based accelerator test facility at KIT. Its main goal is to serve as a platform for a variety of accelerator studies and to generate strong ultra-short THz pulses for photon science. It will also serve as an injector for a Very Large Acceptance compact Storage Ring (VLA-cSR), which will be realized at KIT in the framework of the compact STorage Ring for Accelerator Research and Technology (cSTART) project. To achieve acceleration of electrons in the RF photoinjector and LINAC (from FLUTE) with high stability, it is necessary to provide stable RF power. For this goal, an upgrade of the existing RF system design has been proposed and is currently being implemented. This contribution will report on the updated RF system design and the commissioning status of the new RF system components.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST008  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST009 Simulation Study of a Bunch Compressor for an Accelerator-Based THz Source at the European XFEL FEL, simulation, undulator, radiation 2454
 
  • P. Boonpornprasert, G.Z. Georgiev, M. Krasilnikov, X.-K. Li, A. Lueangaramwong
    DESY Zeuthen, Zeuthen, Germany
 
  The European XFEL has planned to perform pump-probe experiments using its X-ray pulses and THz pulses. A promising concept to provide the THz pulses with a pulse repetition rate identical to that of the X-ray pulses is to generate them using an accelerator-based THz source. The THz source requires a bunch compressor in order to manipulate the longitudinal phase space of the electron bunch to match with various options of THz radiation generation. This paper presents and discusses simulation study of the bunch compressor for the THz source.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST009  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST010 The Frascati DAΦNE LINAC and the Beam Test Facility (BTF) Setups for Irradiation linac, radiation, operation, diagnostics 2457
 
  • C. Di Giulio, F. Cardelli, D. Di Giovenale
    INFN/LNF, Frascati, Italy
  • B. Buonomo, L.G. Foggetta, D. Moriggi
    LNF-INFN, Frascati, Italy
 
  The DAΦNE LINAC could produce bunches of electrons and positrons for the Beam Test Facility. The BTF is used usually for single particle test of detectors but is able to receive up to 1010 particles per second for irradiation test. The DAΦNE LINAC working point could be deeply changed to obtain low energy beam up to 160 MeV with a primary electron beam with enough pulse charge that fulfills irradiation test requirements. A current monitor was installed in the BTF to provide the particle charge per bunch at the users and a flag with the image acquisition system is in operation too, in order to provide a more precise characterization of the beam delivered for the experiments. In this paper the current status and activities of the BTF facility are described.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST010  
About • Received ※ 26 May 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST011 SuperKEKB Electron Positron Injector Linac Upgrade for Higher Charge and Lower Emittance linac, positron, emittance, injection 2461
 
  • K. Furukawa, H. Ego, Y. Enomoto, N. Iida, T. Kamitani, M. Kawamura, S. Matsumoto, T. Matsumoto, T. Miura, M. Satoh, A. Shirakawa, T. Suwada, M. Yoshida
    KEK, Ibaraki, Japan
 
  KEK electron positron injector linac has established simultaneous top-up injections in 2019 for 5 rings of SuperKEKB DR, LER, HER, PF ring and PF-AR as a base of the both elementary particle physics and photon science experiments even under a quite short beam lifetime. It improved the injection stabilities while the SuperKEKB broke the world record of the collision luminosity of the previous project KEKB. As the collision performance improves, the beam-beam effect makes the dynamic aperture shrink, and the beam lifetime reduces further. Thus, it became inevitable for the injector to be upgraded in order to resolve the contradictory improvements of higher charge and lower emittance of injection beams regarding beam wakefield till 2025. The upgrade plan is described including pulsed magnets, an energy compression system, accelerating structures, girders, positron generator and so on.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST011  
About • Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST012 Achievement of 200, 000 Hours of Operation at KEK 7-GeV Electron 4-GeV Positron Injector Linac injection, linac, positron, operation 2465
 
  • K. Furukawa, M. Akemoto, D.A. Arakawa, Y. Arakida, H. Ego, Y. Enomoto, T. Higo, H. Honma, N. Iida, K. Kakihara, T. Kamitani, H. Katagiri, M. Kawamura, S. Matsumoto, T. Matsumoto, H. Matsushita, K. Mikawa, T. Miura, F. Miyahara, H. Nakajima, T. Natsui, Y. Ogawa, S. Ohsawa, Y. Okayasu, T. Oogoe, M.A. Rehman, I. Satake, M. Satoh, Y. Seimiya, T. Shidara, A. Shirakawa, H. Someya, T. Suwada, M. Tanaka, D. Wang, Y. Yano, K. Yokoyama, M. Yoshida, T. Yoshimoto, R. Zhang, X. Zhou
    KEK, Ibaraki, Japan
  • Y. Bando
    Sokendai, Ibaraki, Japan
 
  KEK electron positron injector linac initiated the injection operation into Photon Factory (PF) light source in 1982. Since then for 39 years, it has served for multiple projects, namely, TRISTAN, PF-AR, KEKB, and SuperKEKB. Its total operation time has accumulated 200 thousand hours on May 7, 2020. We are extremely proud of the achievement following continuous efforts by our seniors. The construction of the injector linac started in 1978, and it was commissioned for PF with 2.5 GeV electron in 1982. In parallel, the positron generator linac was constructed for the TRISTAN collider project. The slow positron facility was also commissioned in 1992. After the KEKB asymmetric-energy collider project was commissioned in 1998 with direct energy injections, the techniques such as two-bunch acceleration and simultaneous injection were developed. As the soft structure design of the linac was too weak against the great east Japan earthquake, it took three years to recover. Then the construction and commissioning for the SuperKEKB project went on, and the simultaneous top-up injection into four storage rings contributes to the both elementary particle physics and photon science.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST012  
About • Received ※ 20 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST013 Development of a Detection System for Quasi-Monochromatic THz Pulse by a Spatially Modulated Electron Beam laser, radiation, timing, cathode 2469
 
  • K. Murakoshi, Y. Koshiba, Y. Tadenuma, P. Wang, M. Washio
    Waseda University, Tokyo, Japan
  • R. Kuroda
    AIST, Tsukuba, Japan
  • K. Sakaue
    The University of Tokyo, Graduate School of Engineering, Bunkyo, Japan
 
  We have studied the generation of the broadband THz pulse using a compact linear accelerator. The THz pulse is generated by control of an electron beam angle to Cherenkov radiation angle. In addition, we have succeeded in producing a quasi-monochromatic THz pulse by the spatially modulated electron beam by passing through a slit. This work aims to develop a detection system to elucidate the spectrum of the quasi-monochromatic THz pulse. To detect it stably in a noisy radiation environment, the stability of probe laser system for Electro Optic sampling and timing synchronization system are important. In this conference, the generation method of each THz pulses, the results of development of detection system, and future prospect will be reported.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST013  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST017 Physical Design of a 10 MeV High Scanning Frequency Irradiation Electron Linear Accelerator radiation, gun, simulation, kicker 2476
 
  • S. Zhang, Z.D. Zhang
    UCAS, Beijing, People’s Republic of China
  • Y.L. Chi, M. Iqbal, J.R. Zhang, S. Zhang, Z.D. Zhang, Z.S. Zhou
    IHEP, Beijing, People’s Republic of China
 
  A compact 10 MeV irradiation S-band electron linear accelerator has been proposed to carry out the electron radiation effect test of materials and devices. The Linac includes a standing wave pre-buncher, a traveling wave bunching accelerating structure. The traveling wave accelerating structure uses a 5MW klystron as RF source and provides electron beam energy 3.5-10MeV and average current 0.01-1mA. The required irradiation scanning frequency is very high, up to 100Hz and irradiation area is large (200mm×200mm). To meet the requirements, a novel beam scanning system, including one kicker for horizontal scanning and one magnet for vertical scanning, have been proposed. This paper presents the physical design of the 10MeV electron Linac and beam dynamics simulation results.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST017  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 14 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST018 The Design of a Second Beamline for the CLEAR User Facility at CERN experiment, quadrupole, focusing, dipole 2479
 
  • L.A. Dyks, R. Corsini, P. Korysko
    CERN, Meyrin, Switzerland
  • P. Burrows
    JAI, Oxford, United Kingdom
  • P. Burrows, P. Korysko
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
 
  The CERN Linear Electron Accelerator for Research (CLEAR) has been operating as a general user facility since 2017 providing beams for a wide range of user experiments. However, with its current optical layout, the beams available to users are not able to cover every request. To overcome this, a second experimental beamline has been proposed. In this paper we discuss the potential optics of the new line as well as detailing the hardware required for its construction. Branching from the current beamline, via a dogleg chicane that could be used for bunch compression, the new beamline would provide an additional in-air test stand to be available to users. The beamline before the test stand would utilise large aperture quadrupoles to allow the irradiation of large target areas or strong focussing of beams onto a target. In addition to this there would also be further in-vacuum space to install experiments.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST018  
About • Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST019 Generation of Transversely Uniform Bunches from a Gaussian Laser Spot in a Photoinjector for Irradiation Experiments space-charge, laser, linac, gun 2483
 
  • L.A. Dyks, P. Burrows
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
  • P. Burrows
    JAI, Oxford, United Kingdom
  • R. Corsini, A. Latina
    CERN, Meyrin, Switzerland
 
  Beams of uniform transverse beam profile are desirable for a variety of applications such as irradiation experiments. The generation of beams with such profiles has previously been investigated as a method of reducing emittance growth. These methods, however, often use complicated optics setups or short, femtosecond laser pulse lengths. In this paper, we demonstrate that if ultra low emittance is not the target of the photoinjector, it is possible to produce transversely uniform beam profiles using a simple Gaussian laser, with a bunch length of a few picoseconds, utilising space-charge effects only.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST019  
About • Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST021 Beam Dynamics Simulations of Linear Accelerator for Natural Rubber Vulcanization at Chiang Mai University simulation, linac, gun, cathode 2491
 
  • J. Saisut, S. Rimjaem, C. Thongbai
    Chiang Mai University, Chiang Mai, Thailand
  • M. Jitvisate
    Suranaree University of Technology, Nakhon Ratchasima, Thailand
  • S. Rimjaem, J. Saisut, C. Thongbai
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  The Linear accelerator system for natural rubber vulcanization has been developed at the Plasma and Beam Physics Research Facility, Chiang Mai University, Thailand. The main components of the accelerator system consist of a DC electron gun with a thermionic cathode, an RF linear accelerator, an RF system, a control system, and an irradiation system. The electron beam properties for natural rubber vulcanization are predicted from the beam dynamics simulation starting from a cathode to the titanium exit window. The electron beam generation and the particle in cell simulation inside the DC electron gun are performed using CST Studio Suit software. The electron distribution at the gun exit from the CST output is covered to be an input distribution of the ASTRA beam dynamics simulation program. The electron beam enters linac and is accelerated by RF filed inside the linac. The ASTRA simulation code is used to track electron trajectories including the space-charge interaction and the simulation starts from linac entrance to the exit windows. The electron beam properties for various conditions are evaluated and will be used for further simulations.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST021  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST040 Commissioning of an X-Band Cavity for Longitudinal Phase Space Linearization at UCLA PEGASUS Laboratory cavity, gun, linac, emittance 2533
 
  • P.E. Denham, P. Musumeci, A. Ody
    UCLA, Los Angeles, USA
 
  This paper discusses the commissioning of an X-band (9.6 Ghz) linearizer cavity at the UCLA PEGASUS beamline. The photoinjector gun and booster linac operate at S-band (2.856 GHz) and the linearizer cavity can be used to compensate temporally correlated energy spread inherited by the use of relatively long (many ps) laser pulses at the photocathode. The cavity is comprised of 7 cells for a total length of a 9.45 cm, and is installed in the drift section between the gun and the linac. It can be used to remove higher order correlations and minimize the beam energy spread of 13 ps long beams to 10-4.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST040  
About • Received ※ 08 June 2022 — Revised ※ 21 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOST045 Temperature Dependent Effects on RF Surface Resistivity cavity, cryogenics, experiment, operation 2540
 
  • G.E. Lawler, A. Fukasawa, N. Majernik, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
 
  Funding: This work was supported by DOE Contract DE-SC0020409
A promising future for linear accelerators such as compact free electron lasers and electron positron colliders is higher gradient RF cavities enabled by cryogenic temperature operation. Breakdown rates have been shown empirically to be significantly reduced at low temperatures allowing for higher gradient. The surface physics associated with this observation is complicated and there many remain questions as to the exact phenomena responsible. One major figure of merit that can better inform the theory of breakdown is the RF surface resistivity which can be used to compute for example the RF pulse heating during operation. We then use techniques developed for previous Xband and Sband low power surface resistivity measurement by way of temperature dependent quality factor measurements to study Cband cavities. We first present a review of low temperature effects that may be responsible for the change in surface resistivity at low temperature. We then explain some of the initial measurements of these low power RF quality factor tests and compare them to a review some of the physical phenomena that could determine the low temperature surface effects.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST045  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT004 Design of a Compact 180-Degree Single-Shot Energy Spectrometer Based on a Halbach Dipole Magnet dipole, vacuum, simulation, detector 2564
 
  • R. Bazrafshan, T. Rohwer
    Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
  • M. Fakhari, N.H. Matlis
    CFEL, Hamburg, Germany
  • F.X. Kaernter
    DESY, Hamburg, Germany
 
  In the AXSIS project at DESY, we develop compact THz accelerating structures for a table-top x-ray source. Acceleration is achieved by passing the electron beam through a dielectric-loaded waveguide powered by multi-cycle THz radiation. The final electron energy strongly depends on THz-power injected into the LINAC and timing. Thus in first experiments we expect large energy fluctuations and a large range of energies to cover. We designed an electron energy spectrometer for a wide range of final energies covering 5 to 20 MeV in a single-shot. Here, we present the design of an energy spectrometer which uses a compact dipole magnet based on the Halbach array concept to deflect the electron beam through a 180° path intercepted by a Fiber Optic Scintillator (FOS) mounted inside the vacuum perpendicular to the beam. The 180-degree bending geometry provides the possibility of having the focus point of all energies at the same distance from the magnet edge which makes the design simpler and more compact. It also removes the necessity of installing a safety dipole at the end of the accelerator. A slit system at the spectrometer entrance increases resolution to better than 0.2%.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT004  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT005 Field Enhanced, Compact S-Band Gun Employing a Pin Cathode gun, cathode, cavity, multipactoring 2567
 
  • R. Bazrafshan, T. Rohwer
    Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
  • M. Fakhari, K. Flöttmann, F.X. Kaernter
    DESY, Hamburg, Germany
  • N.H. Matlis
    CFEL, Hamburg, Germany
 
  S-band RF-guns are highly developed for production of low emittance relativistic electron bunches, but need powerful klystrons for driving. Here, we present the design and first experimental tests of a compact S-band gun, which can accelerate electrons up to 180 keV powered by only 10 kW from a compact rack-mountable solid-state amplifier. A pin-cathode is used to enhance the RF electric field on the cathode up to 100 MV/m as in large-scale S-band guns. An electron bunch is generated through photoemission off a flat copper surface on the pin excited by a UV laser pulse followed by a focusing solenoid producing a low emittance bunch with 0.1 mm mrad transverse emittance for up to 100 fC bunch charge. We are currently in the conditioning phase of the gun and first experiments show good agreement with simulations. The compact gun will serve three purposes: (i) it can be used directly for ultrafast electron diffraction; (ii) as an injector into a THz booster producing 0.3MeV to 2 MeV electron bunches for ultrafast electron diffraction; (iii) The system in (ii) serves as an injector into a THz linear accelerator producing a 20 MeV beam for the AXSIS X-ray source project.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT005  
About • Received ※ 21 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT007 High Bunch Charges in the Second Injection Beamline of MESA dipole, simulation, operation, acceleration 2574
 
  • A.A. Kalamaiko, K. Aulenbacher, M.A. Dehn, S. Friederich, C.P. Stoll
    KPH, Mainz, Germany
 
  MESA (Mainz Energy-recovering Superconducting Accelerator) is an accelerator with two laser-driven electron sources (polarized and unpolarized) operating at 100 kV which is under construction at the Johannes Gutenberg University in Mainz. The unpolarized electron source MIST (MESA Injector Source Two) allows to produce high charged electron bunches with charge up to 7.7 pC. This source and a Mott polarimeter will be arranged on the same height above the MESA injector main beamline. A parallel shifting beamline was developed which allows to transport high charged beam from the source MIST to the main MESA beamline. Moreover, the designed beamline allows to transport beam from the electron source STEAM to the Mott polarimeter. This report is dedicated to the design of the separation beamline which transports and compresses highly charged electron bunches from the electron source MIST to the first acceleration section of MESA.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT007  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT009 Dependency Measurement of BPM Reading in the HLS-II Storage Ring operation, storage-ring, feedback, electronics 2580
 
  • G. Wang, K.M. Chen, G. Feng, M. Hosaka, Z. Wang, W. Xu
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
  • L. Guo
    Nagoya University, Nagoya, Japan
  • S.W. Wang
    DLS, Oxfordshire, United Kingdom
 
  Beam orbit stability is essential for the operation of the storage ring based light sources. Orbit feedback systems are commonly adopted to maintain the beam on a reference orbit. However, the BPM reading could be affected by its temperature, beam current, etc, which leads to shift of the beam reference orbit. Online experiment is carried out in the HLS-II storage ring to study the dependence of the beam reference orbit on the BPM temperature and beam current. The result shows that the average change of BPM readings due to BPM temperature is about 37.4 ’m/’C horizontally and 11.5 ’m/’C vertically. The average change of BPM readings induced by beam current is about 0.27 ’m/mA horizontally and 0.20 ’m/mA vertically.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT009  
About • Received ※ 19 May 2022 — Revised ※ 23 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT015 The Design of the Full Energy Beam Exploitation (FEBE) Beamline on CLARA experiment, laser, diagnostics, FEL 2594
 
  • A.R. Bainbridge, D. Angal-Kalinin, J.K. Jones, T.H. Pacey, Y.M. Saveliev, E.W. Snedden
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
 
  The CLARA facility at Daresbury Laboratory was orig-inally designed for the study of novel FEL physics utilis-ing high-quality electron bunches at up to 250 MeV/c. To maximise the exploitation of the accelerator complex, a dedicated full energy beam exploitation (FEBE) beam-line has been designed and is currently being installed in a separate vault on the CLARA accelerator. FEBE will allow the use of high charge (up to 250 pC), moderate energy (up to 250 MeV), electron bunches for a wide variety of accelerator applications critical to ongoing accelerator development in the UK and international communities. The facility consists of a shielded enclo-sure, accessible during beam running in CLARA, with two very large experimental chambers compatible with a wide range of experimental proposals. High-power laser beams (up to 100 TW) will be available for electron-beam interactions in the first chamber, and there are concrete plans for a wide variety of advanced diagnostics (includ-ing a high-field permanent magnet spectrometer and dielectric longitudinal streaker), essential for multiple experimental paradigms, in the second chamber. FEBE will be commissioned in 2024.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT015  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT017 Orbit Stability Studies for the Diamond-II Storage Ring power-supply, storage-ring, cavity, resonance 2602
 
  • I.P.S. Martin, C.A. Abraham, D. Crivelli, H. Ghasem, B. Nicholson, T. Olsson, P. Sanchez Navarro
    DLS, Oxfordshire, United Kingdom
 
  The photon-beam positional stability relative to the beam size is a key performance parameter for storage ring light sources. The natural emittance of the Diamond-II ring will be lowered by a factor 16.7 compared to the existing ring, so the absolute stability requirement for the electron beam must reduce accordingly. In addition, advances in detector speed and resolution mean the tolerances are tighter compared to previous generations of storage rings, with a target of 3 % of beam size up to 1 kHz having been adopted for Diamond-II. In this paper we present studies of how the anticipated ground vibrations, girder motion and power supply ripple will affect the electron beam stability as a function of frequency.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT017  
About • Received ※ 08 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 06 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT019 Multi-Alkali Antimonide Photocathode Development for High Brightness Beams cathode, SRF, brightness, gun 2610
 
  • S. Mistry, T. Kamps, J. Kühn, C. Wang
    HZB, Berlin, Germany
  • T. Kamps
    HU Berlin, Berlin, Germany
  • C. Wang
    University Siegen, Siegen, Germany
 
  Funding: This work is funded by the DFG CO 1509/10-1 | MI 2917/1-1
Photocathode R&D at the Helmholtz-Zentrum Berlin (HZB) is driven by the motivation to produce high brightness electron beams for the SRF photoinjector test facility, Sealab/ bERLinPro. Multi-alkali antimonides are the choice photocathode material due to high quantum efficiency (QE) and low intrinsic emittance in the visible range. In this work a more robust alternative to the tried and tested Cs-K-Sb is considered. Na-K-Sb offers similar advantages to Cs-K-Sb including, high QE at green wavelengths but moreover, it offers excellent stability at elevated temperatures. This property could lengthen the cathode lifetime by enhancing the robustness of the photocathode inside the SRF gun. In this work, a status report showcasing first results towards the development of a growth procedure for Na-K-Sb is presented by means of spectral response and XPS measurements conducted in the HZB photocathode lab.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT019  
About • Received ※ 03 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT020 Status and Plans for the New CLS Electron Source Lab gun, operation, linac, radiation 2614
 
  • M.J. Boland, D. Bertwistle, F. Le Pimpec
    CLS, Saskatoon, Saskatchewan, Canada
  • X.F.D. Stragier
    TUE, Eindhoven, The Netherlands
 
  The Canadian Light Source (CLS) has recently created a new Electron Source Lab (ESL) that can run independently from user operations. A section of the old Saskatchewan Accelerator Laboratory experimental nuclear physics tunnels has been rebuilt with new shielding and a separate entrance. The laboratory will be used to prepare an operational spare electron gun for the 250 MeV linac. In addition, there are plans to develop RF guns for a future branch line to inject into the linac and for possible short pulse production. This paper will give an overview of the ESL space and the first electron guns which plan to be installed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT020  
About • Received ※ 16 June 2022 — Revised ※ 29 June 2022 — Accepted ※ 04 July 2022 — Issue date ※ 08 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT023 Flexible Features of the Compact Storage Ring in the cSTART Project at Karlsruhe Institute of Technology storage-ring, lattice, sextupole, scattering 2620
 
  • A.I. Papash, A. Bernhard, E. Bründermann, D. El Khechen, B. Härer, A.-S. Müller, R. Ruprecht, J. Schäfer, M. Schwarz
    KIT, Karlsruhe, Germany
 
  Within the cSTART project (compact storage ring for accelerator research and technology), a Very Large Acceptance compact Storage Ring (VLA-cSR) will be realized at the Institute for Beam Physics and Technology (IBPT) of the Karlsruhe Institute of Technology. (KIT). A modified geometry of a compact storage ring operating at 50 MeV energy range has been studied and main features of the new model are described here. The new design, based on 45° bending magnets, is suitable to store a wide momentum spread beam as well as ultra-short electron bunches in the sub-ps range injected from the plasma cell as well as from the Ferninfrarot Linac- Und Test Experiment (FLUTE). The DBA lattice of the VLA-cSR with different settings and relaxed parameters, split elements and higher order optics of tolerable strength allows to improve the dynamic aperture and momentum acceptance to an acceptable level. This contribution discusses the lattice features in detail, expected lifetime, injection, tolerances and different possible operation schemes of the ring.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT023  
About • Received ※ 20 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 02 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT024 MIST - The MESA-Injector Source Two cathode, booster, laser, simulation 2624
 
  • M.A. Dehn, P.S. Plattner
    IKP, Mainz, Germany
  • K. Aulenbacher
    HIM, Mainz, Germany
  • K. Aulenbacher
    GSI, Darmstadt, Germany
  • K. Aulenbacher
    KPH, Mainz, Germany
 
  Funding: Work supported by the German science ministry BMBF through Verbundforschung
The new accelerator MESA (Mainz Energy Recovering Superconducting Accelerator) will provide an average CW electron beam current of up to 10 mA. Operating at 1.3 GHz, this corresponds to a bunch charge of 7.7 pC. The new DC photoemission source MIST is optimized for these requirements. A challenge is heating of the photocathode at high laser power. By a suitable mechanical construction and the use of specific materials, the heat can be dissipated during operation. Options for further improvements are discussed.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT024  
About • Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT025 Photocathode Stress Test Bench at INFN LASA cathode, laser, gun, operation 2627
 
  • D. Sertore, D. Giove, L. Monaco
    INFN/LASA, Segrate (MI), Italy
  • A. Bacci, F. Canella, S. Cialdi, I. Drebot, D. Giannotti, L. Serafini
    INFN-Milano, Milano, Italy
  • D. Cipriani, E. Suerra
    Università degli Studi di Milano, Milano, Italy
  • G. Galzerano
    POLIMI, Milano, Italy
  • G. Guerini Rocco
    Università degli Studi di Milano & INFN, Segrate, Italy
 
  A UHV test bench based on a 100 kV DC gun and a 100 MHz repetition rate laser has been setup up at INFN LASA to test Cs2Te photocathodes. This operation mode is the baseline of the BriXSinO project, currently in the design phase in our laboratory, and the qualification of the Cs2Te photocathodes is a key issue. In this paper, we present the recent advances in the different aspects of this R&D activity.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT025  
About • Received ※ 10 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT026 Assembly and Characterization of Low-Energy Electron Transverse Momentum Measurement Device (TRAMM) at INFN LASA cathode, emittance, laser, site 2630
 
  • D. Sertore, M. Bertucci, A. Bosotti, D. Giove, L. Monaco, R. Paparella
    INFN/LASA, Segrate (MI), Italy
  • G. Guerini Rocco, C. Pagani
    Università degli Studi di Milano & INFN, Segrate, Italy
 
  In the framework of high-brightness electron beam generation, thermal emittance is nowadays a key parameter. While alkali tellurides are extensively used in advanced electron sources, alkali antimonides photocathodes demonstrated high QE in the visible, thus making feasible CW operations for RF-based photoinjectors. The INFN LASA laboratory in Milan is fully equipped with dedicated production systems for photocathode preparation and optical setup for QE evaluation. In this paper, we describe a newly designed device dedicated to electron transverse momentum measurement (TRAMM). It will be connected to the main production chambers and will serve as an "emittance monitoring" system during photocathode growth. From the design phase, through the parameter estimate, assembly of the components, to the installation and first measurements, we describe the status of this project and its future developments.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT026  
About • Received ※ 09 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 07 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT027 R&D on High QE Photocathodes at INFN LASA cathode, gun, FEL, operation 2633
 
  • D. Sertore, M. Bertucci, L. Monaco
    INFN/LASA, Segrate (MI), Italy
  • G. Guerini Rocco
    Università degli Studi di Milano & INFN, Segrate, Italy
  • S.K. Mohanty, H.J. Qian, F. Stephan
    DESY Zeuthen, Zeuthen, Germany
 
  We present the recent activities on antimonide and telluride alkali based photocathodes at INFN LASA. The R&D on Cs2Te materials is focused on investigating effects of material thickness and growth procedures on the photocathodes performances during operation in RF guns. We aim to improve thermal emittance and long term stability of these films. The more recent work on alkali antimonide showed the need for substantial improvements in stability and QE during operation. We present here our recent achievements and plans for future activities.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT027  
About • Received ※ 09 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT028 Dependence of CsK2Sb Photocathode Performance on the Quality of Graphene Substrate Film cathode, laser, synchrotron, synchrotron-radiation 2637
 
  • L. Guo, K. Goto, Y. Takashima
    Nagoya University, Nagoya, Japan
  • H. Yamaguchi
    LANL, Los Alamos, New Mexico, USA
  • M. Yamamoto
    KEK, Ibaraki, Japan
 
  Funding: U.S.-Japan Science and Technology Cooperation Program in High Energy Physics
A photocathode that extracts electrons by irradiating a semiconductor or metal with a laser is applied to advanced accelerators and electron microscopes as a high-performance cathode. In particular, the CsK2Sb photocathode is of interest because it has features such as low emittance, excitability with visible light, and high quantum efficiency. Generally, the CsK2Sb photocathode is produced by depositing a cathode element on a substrate, so that the cathode performance strongly depends on the surface condition of the substrate. We have found graphene as reusable substrate, which has the property of being chemically inactive. In this study, graphene film quality dependence of CsK2Sb photo-cathode performance was evaluated. Specifically, CsK2Sb cathode was deposited using different quality graphene film substrates and their QE values and uniformity were compared. The quality of graphene films was analyzed using X-ray Photoelectron Spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). We found that the graphene film can be cleaned by heating at 500 deg. The QE of the cathode on a good quality graphene film was higher and more uniform than that on a poor quality graphene film.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT028  
About • Received ※ 16 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 10 June 2022 — Issue date ※ 24 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT029 Study on the Performance Improvement of Alkali Antimonide Photocathodes for Radio Frequency Electron Guns cathode, experiment, ECR, laser 2640
 
  • R. Fukuoka, K. Ezawa, Y. Koshiba, M. Washio
    Waseda University, Tokyo, Japan
  • K. Sakaue
    The University of Tokyo, Graduate School of Engineering, Bunkyo, Japan
 
  Semiconductor photocathodes such as Cs-Te and Cs-K-Sb are used as electron sources in accelerators to generate high brightness beams using radio frequency (rf) electron guns. Alkali antimonide photocathodes have a high quantum efficiency (Q.E.) of ~10%, and their excitation wavelength is in the visible light region (532 nm), so that they are expected to reduce the requirements on the optical system and increase the amount of charge compared to Cs-Te. However, alkali antimonide photocathodes have a short lifetime and degrade under poor vacuum conditions, so it is essential to improve durability by protective film coatings. Therefore, we are currently working on the fabrication of high Q.E. alkali antimonide photocathodes that can withstand the Q.E. reduction during coating. In this presentation, we will report the results of comparison between the fabricated alkali antimonide photocathode and Cs-Te photocathode, and future prospects.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT029  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 09 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT030 Design Study of 30 MeV Linac for a Compact THz Radiation Source linac, radiation, ion-source, impedance 2643
 
  • S. Jummunt, S. Chunjarean, N. Juntong, S. Klinkhieo
    SLRI, Nakhon Ratchasima, Thailand
  • K. Manasatitpong
    Synchrotron Light Research Institute (SLRI), Muang District, Thailand
 
  Funding: This work is supported by Science, Research, and Innovation Fund (SRI Fund)
A compact THz radiation source plays a possibility to achieve intense THz radiation at tunable frequencies between 0.5 and 5.0 THz, with a peak power of several MW and narrow-bandwidth. This source requires essentially the reliable high gradient s-band linear accelerator (linac) to provide an electron beam energy up to 30 MeV with high bunch charge. In order to obtain a high gradient linac mentioned, the cavity structure has been optimized and performed using the software CST. The preliminary design of linac and beam dynamics study are presented in this paper.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT030  
About • Received ※ 14 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 16 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT033 Performance Characterisation at Daresbury Laboratory of Cs-Te Photocathodes Grown at CERN cathode, emittance, vacuum, cryogenics 2653
 
  • L.A.J. Soomary, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • C. Benjamin, H.M. Churn, L.B. Jones, T.C.Q. Noakes
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • C. Benjamin
    University of Warwick, Coventry, United Kingdom
  • E. Chevallay, V.N. Fedosseev, E. Granados, M. Himmerlich, H. Panuganti
    CERN, Meyrin, Switzerland
  • L.B. Jones, T.C.Q. Noakes, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  Funding: STFC Doctoral Training Studentship
The search for high-performance photocathodes is a priority in the field of particle accelerators. The surface characteristics of a photocathode affect many important factors of the photoemission process including the photoemission threshold, the intrinsic emittance and the quantum efficiency. These factors in turn define the electron beam quality, which is measurable using figures of merit like beam emittance, brightness and energy spread. We present characterisation measurements for four caesium telluride photocathodes synthesized at CERN. The photocathodes were transported under ultra-high vacuum (UHV) and analysed at STFC Daresbury Laboratory, using ASTeC’s Multiprobe (SAPI)* for surface characterisation via XPS and STM, and for Mean Transverse Energy (MTE) measurements using the Transverse Energy Spread Spectrometer (TESS)**. The MTE measurements were estimated at cryogenic and room temperatures based on the respective transverse energy distribution curves. We discuss correlations found between the synthesis parameters, and the measured surface characteristics and MTE values.
*B.L. Militsyn, 4-th EuCARD2 WP12.5 meeting, Warsaw, 14-15 March 2017
**L.B. Jones et al., Proc. FEL ’13, TUPPS033, 290-293; https://accelconf.web.cern.ch/FEL2013/papers/tupso33.pdf
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT033  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT034 Controlled Degradation of a Ag Photocathode by Exposure to Multiple Gases cathode, experiment, emittance, factory 2657
 
  • L.A.J. Soomary, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • L.B. Jones, T.C.Q. Noakes, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • L.B. Jones, T.C.Q. Noakes
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
 
  Funding: STFC Doctoral Training Studentship
The search for high performance photocathode electron sources is a priority in the accelerator science community. The surface characteristics of a photocathode define many important factors of the photoemission process including the work function, the intrinsic emittance and the quantum efficiency of the photocathode. These factors in turn define the ultimate electron beam quality, which is measurable as normalised emittance, brightness and energy spread. Strategies for improving these parameters vary, but understanding and influencing the relevant cathode surface physics which underpin these attributes is a primary focus for the community*. We present performance data under illumination at 266 nm for Ag (100) single-crystal cathode and a Ag polycrystalline cathode after progressive exposure to O2, CO2, CO and N2 using our TESS** instrument both at room and cryogenic temperatures. Crucially the data shows the effect of progressive degradation*** in the photocathode performance as a consequence of exposure to controlled levels of O2 and that exposing an oxidized Ag surface to CO can drive partial QE recovery.
*K.L. Jensen; Appl. Phys. Lett. 89, 224103 (2006);
**L.B. Jones et al.; Proc. FEL ’13, TUPPS033, 290-293;
***N. Chanlek et al.; J. Phys. D: Appl. Phys. (2014) 47, 055110;
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT034  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT037 Ceramics Evaluation for MW-Power Coaxial Windows, Operating in UHF Frequency Range Windows, vacuum, multipactoring, cavity 2668
 
  • S.V. Kutsaev, R.B. Agustsson, P.R. Carriere, N.G. Matavalam, A.Yu. Smirnov, S.U. Thielk
    RadiaBeam, Santa Monica, California, USA
  • A.A. Haase
    SLAC, Menlo Park, California, USA
  • T.W. Hall, D. Kim, J.T.M. Lyles, K.E. Nichols
    LANL, Los Alamos, New Mexico, USA
 
  Funding: This work was supported by the U.S. Department of Energy, Office of Basic Energy Science, under SBIR grant DE- SC0021552
Modern accelerator facilities require reliable high-power RF components. The RF vacuum window is a critical part of the waveguide couplers to the accelerating cavities. It is the point where the RF feed crosses the vacuum boundary and thus forms part of the confinement barrier. RF windows must be designed to have low power dissipation inside their ceramic, be resistant to mechanical stresses, and free of discharges. In this paper, we report on the evaluation of three different ceramic candidates for high power RF windows. These materials have low loss tangents, low secondary electron yield (SEY), and large thermal expansion coefficients. The acquired materials were inspected, coated, and measured to select the optimal set.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT037  
About • Received ※ 01 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT044 The Alkali-Metal Photocathode Preparation Facility at Daresbury Laboratory: First Caesium Telluride Deposition Results cathode, MMI, emittance, FEL 2693
 
  • H.M. Churn, C. Benjamin, L.B. Jones, T.C.Q. Noakes
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • C. Benjamin
    University of Warwick, Coventry, United Kingdom
  • H.M. Churn, L.B. Jones, T.C.Q. Noakes
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
 
  Fourth generation light sources require high brightness electron beams. To achieve this a photocathode with a high quantum efficiency and low intrinsic emittance is required, which is also robust with a long operational lifetime and low dark current. Alkali-metal photocathodes have the potential to fulfil these requirements, so are an important research area for the accelerator physics community. STFC Daresbury Laboratory are currently commissioning the Alkali-metal Photocathode Preparation Facility (APPF) which will be used to grow alkali photocathodes. Photocathodes produced by the APPF will be analysed using Daresbury Laboratory’s existing Multiprobe system* and the Transverse Energy Spread Spectrometer (TESS)**. Multiprobe can perform a variety of surface analysis techniques while the TESS can measure the Mean Transverse Energy of a photocathode from its Transverse Energy Distribution Curve over a large range of illumination wavelengths. We present an overview on our current progress in the commissioning and testing of the APPF, the results from the first Cs-Te deposition and detail the work planned to facilitate the manufacture of Cs2Te photocathodes for the CLARA accelerator***.
*B.L. Militsyn, 4th EuCARD2 WP12.5 meeting, Warsaw, 14-15 Mar. 2017
**L. Jones et al., Proc. FEL ’13, TUPPS033, 290-293
***D. Angal-Kalinin et al., Phys. Rev. Accel. Beams, Vol. 23, Iss. 4, 2020
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT044  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT045 OPAL Simulations of the MESA Injection System simulation, solenoid, quadrupole, experiment 2697
 
  • S. Friederich
    IKP, Mainz, Germany
  • K. Aulenbacher
    HIM, Mainz, Germany
  • K. Aulenbacher
    GSI, Darmstadt, Germany
  • K. Aulenbacher, C.P. Stoll
    KPH, Mainz, Germany
 
  Funding: This work is supported by the DFG excellence initiative PRISMA+.
The MESA injection system will produce the spin-polarized electron beam for the upcoming accelerator MESA in Germany. The photoemission electron source (STEAM) will deliver 150 uA of spin-polarized electrons from GaAs-based photocathodes for the P2 experiment. Afterwards the low-energy beam transportation system (MELBA) can rotate the spin using two Wien filters and a solenoid for polarization measurements and to compensate for the spin precession in MESA. A chopper and buncher system prepares the phase space for the first acceleration in the normal-conducting pre-booster MAMBO. First OPAL simulation results of MELBA were presented at IPAC’21. Meanwhile these simulations have been extended by a 270-degree-bending alpha magnet as well as the electrostatic and magnetostatic fieldmaps of the Wien filters. Furthermore the fieldmaps of the 4 modules of the pre-accelerator MAMBO have been implemented. Hence, the complete MESA injection system could be simulated in OPAL and the results will be shown.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT045  
About • Received ※ 30 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT048 Impact of IDs on the Diamond Storage Ring and Application to Diamond-II photon, storage-ring, feedback, emittance 2705
 
  • R.T. Fielder, B. Singh
    DLS, Oxfordshire, United Kingdom
 
  When investigating the effect of insertion devices (IDs) on storage ring operations, it is not possible to simulate all of the large number of gap, phase and field settings that are available. This can be of particular concern for transient effects in IDs that are moved frequently, or APPLE-II devices which may use many different polarisation states. We therefore present measurements of the impact of selected IDs on various parameters in the current Diamond storage ring including orbit distortion, tunes, chromaticity and emittance, and assess the expected impact when applied to the Diamond-II lattice.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT048  
About • Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT061 European XFEL Undulators - Status and Plans undulator, FEL, photon, radiation 2737
 
  • S. Casalbuoni, S. Abeghyan, J.E. Baader, U. Englisch, V. Grattoni, S. Karabekyan, B. Marchetti, H. Sinn, F. Wolff-Fabris, M. Yakopov, P. Ziolkowski
    EuXFEL, Schenefeld, Germany
 
  European XFEL has three undulator lines based on permanent magnet technology: two for hard and one for soft X-rays. The planar undulators can be tuned to cover the acceptance in terms of photon beam energy of the respective photon beamlines: 3.6-25 keV (SASE1/2) and 0.25-3 keV (SASE3) by changing the electron energy range between 11.5 GeV and 17.5 GeV and/or the undulator gap. In order to obtain different polarization modes, as required by the soft X-ray beamlines, a helical afterburner consisting of four APPLE X undulators designed by PSI has been installed at the downstream end of the present SASE3 undulator system. The European XFEL plans to develop the technology of superconducting undulators, which is of strategic importance for the facility upgrade. In order to extend the energy range above 30 keV a superconducting undulator afterburner is foreseen to be installed at the end of SASE2. This contribution presents the current status and the planned upgrades of the undulator lines at European XFEL.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT061  
About • Received ※ 07 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT063 Design of Scilab Xcos Simulation Model for Pulsed Wire Method Data Analyses undulator, experiment, simulation, radiation 2741
 
  • H. Jeevakhan
    NITTTR, Bhopal, India
  • S.M. Khan, G. Mishra
    Devi Ahilya University, Indore, India
 
  Pulsed wire method (PWM)is used for undulator characterisation. Scilab Xcos simulation model is designed for the analyses of data obtained by PWM. The data obtained from PWM is given as input to the model and its output gives the magnetic field of the undulator. Scilab Xcos model can also be utilized for determining the phase error of the undulator.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT063  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 09 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT065 Operation of X-Ray Beam Position Monitors with Zero Bias Voltage at Alba Front Ends photon, operation, background, radiation 2747
 
  • J. Marcos, U. Iriso, V. Massana, R. Monge, D. Yépez
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  Blade-type X-ray Beam Position Monitors (XBPMs) are customarily operated with a negative bias voltage applied to the blades in order to prevent the transference of photoelectrons between the blades, and hence to maximize the signal at each blade and to avoid cross-talk. This was the selected approach at ALBA since the start of its operation for users in 2012. However, over the years the insulation provided by the ceramic pieces separating the blades from the support structure has degraded progressively, giving rise to an ever-increasing leakage current not related with the photon beam to be monitored. On 2020 the level of these leak currents had already become comparable to the photocurrents generated by the photon beam itself, making the readings from many of the XBPMs unreliable. Following the example from other facilities, we decided to remove the bias voltage from the blades and to test the performance of the XBPMs under these conditions, with such good results that we apply this method also for the new, non degraded, XBPMs. In this paper we present the approach used at ALBA to analyse XBPM data, and our experience operating them with zero bias voltage.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT065  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT066 Helical Wiggler Design for Optical Stochastic Cooling at CESR wiggler, simulation, storage-ring, permanent-magnet 2751
 
  • V. Khachatryan, M.B. Andorf, I.V. Bazarov, J.A. Crittenden, S.J. Levenson, J.M. Maxson, D.L. Rubin, J.P. Shanks, S. Wang
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • W.F. Bergan
    BNL, Upton, New York, USA
 
  Funding: The authors thank the Center for Bright Beams, NSF award PHY-1549132; W.F.B. was supported by the NSF Graduate Research Fellowship Program under grant number DGE-1650441.
A helical wiggler with parameter kund=4.35 has been designed for the Optical Stochastic Cooling (OSC) experiment in the Cornell Electron Storage Ring (CESR). We consider four Halbach arrays, which dimensions are optimized to get the required helical field profile, as well as, to get the best Dynamic Aperture (DA) in simulations. The end poles are designed with different dimensions to minimize the first and second field integrals to avoid the need of additional correctors for the beam orbit. The design is adopted to minimize the risks for the magnet blocks demagnetization. To quantify the tolerances, we simulated the effects of different types of geometrical and magnetic field errors on the OSC damping rates. In addition, to understand the challenges for the construction, as well as, to validate the model field calculations, we prototyped a small two period version. The prototype field is compared to the model, and the results are presented in this work.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT066  
About • Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 14 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK010 Development of a Short Period Superconducting Helical Undulator undulator, FEL, photon, simulation 2788
 
  • A.G. Hinton
    STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
  • J. Boehm, L. Cooper, B. Green, T. Hayler, P. Jeffery, C.P. Macwaters, B.J.S. Matthews
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • S. Milward
    DLS, Oxfordshire, United Kingdom
  • B.J.A. Shepherd, N. Thompson
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
 
  Superconducting technology provides the possibility to develop short period, small bore undulators that can generate much larger magnetic fields than alternative technologies. This may allow an XFEL with optimised superconducting undulators to cover a broader range of wavelengths than traditional undulators. At STFC, we have undertaken work to design and build a prototype superconducting helical undulator module with parameters suitable for use on a future XFEL facility. This work includes the design of an undulator with 13 mm period and 5 mm magnetic gap, as well as the supporting cryogenic and vacuum systems required for operation. We present here the updated design of the superconducting helical undulator that represents the results of prototyping work. Improved methods for manufacturing the undulator former and winding the superconducting wire have been developed. The measured mechanical tolerances and the impact on the field quality will be presented. The fields produced by prototype undulators will soon be measured using a Hall probe system.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK010  
About • Received ※ 06 June 2022 — Accepted ※ 10 June 2022 — Issue date ※ 17 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK014 100 keV Electron Source Design for the New 3 GeV Synchrotron Facility in Thailand gun, cathode, focusing, simulation 2800
 
  • N. Juntong, S. Bootiew, T. Chanwattana, Ch. Dhammatong, S. Jummunt, K. Kittimanapun, W. Phacheerak
    SLRI, Nakhon Ratchasima, Thailand
  • K. Manasatitpong
    Synchrotron Light Research Institute (SLRI), Muang District, Thailand
 
  The Synchrotron Light Research Institute (SLRI) is developing a new synchrotron light source with an electron beam energy of 3 GeV. The DC thermionic electron gun was chosen because it is simple and less cost. The design process is well known. The operation is more stable compared to the RF gun. The cathode Y-646B was considered because it had already been used at the old synchrotron machine and the possibility of sharing the stock outweighs other disadvantages. Moreover, it is used in many synchrotron facilities, so it is easy to find references. The present of the focusing electrode was discussed. The focusing electrode will increase the complexity of the gun, but it is necessary to get a high-quality beam from the gun. The designed electron gun can produce 1.1 A beams current with the normalized emittance of 0.910 Pi·mm·mrad, which satisfied the requirement of the linac injector. The design and study results will be discussed in this report.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK014  
About • Received ※ 20 May 2022 — Accepted ※ 14 June 2022 — Issue date ※ 29 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK015 Solid-State Pulsed Power Supply for a 100 keV Electron Source of the New Synchrotron Facility in Thailand gun, high-voltage, power-supply, simulation 2803
 
  • W. Phacheerak, S. Bootiew, T. Chanwattana, Ch. Dhammatong, N. Juntong, K. Kittimanapun
    SLRI, Nakhon Ratchasima, Thailand
  • K. Manasatitpong
    Synchrotron Light Research Institute (SLRI), Muang District, Thailand
 
  The new synchrotron light source project in Thailand will utilize a thermionic DC electron gun. The maximum operation of the gun is 100 keV, which requires a pulsed power supply of 100kV. The present synchrotron machine uses a conventional design of the gun power supply. To improve the high voltage pulsed quality, the solid-state design of the gun power supply is utilized. The output pulse width can be adjusted easily and the droop is less compared to the conventional design. The designed output of 100 kV amplitude with 5 µs pulsed width can be achieved with this design. It also produces a less droop of 1.8%. The design process and results will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK015  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK023 Ferrite Specification for the Mu2e 300 kHz and 4.4 MHz AC Dipole Magnets proton, dipole, experiment, target 2816
 
  • K.P. Harrig, E. Prebys
    UCD, Davis, California, USA
  • L. Elementi, C.C. Jensen, H. Pfeffer, D.A. Still, I. Terechkine, S.J. Werkema, M. Wong
    Fermilab, Batavia, Illinois, USA
 
  Funding: Work supported by by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, in addition to grant DE-SC0019254.
The Mu2e experiment at Fermilab will measure the rate for neutrinoless-conversion of negative muons into electrons with never-before-seen precision. This experiment will use a pulsed 8 GeV proton beam with pulses separated by 1.7 µs. To suppress beam induced backgrounds to this process, a set of dipoles operating at 300 kHz and 4.4 MHz have been developed that will reduce the fraction of out-of-time protons at the level of 1E-10 or less. Selection of magnetic ferrite material for construction must be carefully considered given the high repetition rate and duty cycle that can lead to excess heating in conventional magnetic material. A model of the electromagnetic and thermal properties of candidate ferrite materials has been constructed. Magnetic permeability, inductance, and power loss were measured at the two operating frequencies in toroidal ferrite samples as well as in the ferrites from which prototype magnets were built. Additionally, the outgassing rates of the ferrite material was measured to determine vacuum compatibility. The outcome of this work is a detailed specification of the electrical and mechanical details of the ferrite material required for this application.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK023  
About • Received ※ 30 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK027 Temperature Dependent Effects on Quality Factor in C-band RF Cavities cavity, cryogenics, vacuum, shielding 2826
 
  • J.R. Parsons, A. Fukasawa, G.E. Lawler, N. Majernik, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
 
  Funding: This work was supported by DOE Contract DE-SC0020409
Cryogenic operation and associated skin effects are encouraging fields of study for increasing RF gradients of beams within cavities and decreasing the required size for linear accelerators such as free electron lasers. Notably, a cavity’s RF quality factor Q, the ratio of the outgoing RF signal power to the input power, is theoretically multiplied by over 4 when subjected to cryogenic temperatures. Precise measurements of this Q factor require defining a cryostat unit, which consists of a high vacuum chamber, a coldhead, and MLI shielding. We optimized the cryostat by running several cool down tests at high vacuum, incorporating different geometries of MLI shielding to achieve the lowest possible temperatures. We then performed a low power C-band test after installing a cylindrical copper RF cavity to measure the Q factor. Finally, we improved stability and amplification within the chamber by installing edge welded bellows to the coldhead to reduce vibrations. These measurements provide a basis for the development of cryogenic infrastructure to sustain a cryogenic temperature environment for future RF applications.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK027  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 27 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK029 Role of Surface Chemistry in Conditioning of Materials in Particle Accelerators radiation, ECR, site, multipactoring 2829
 
  • G. Sattonnay, S. Bilgen, S. Della Negra, D. Longuevergne, B. Mercier, I. Ribaud
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
 
  For the vacuum scientists and the accelerator community, finding solutions to mitigate pressure rises induced by electron, photon and ion desorption and beam instabilities induced by ion and electron clouds is a major issue. Along the time, changes in the surface chemistry of vacuum chambers are observed during beam operations in particle accelerators, leading to modifications of: outgassing rates, stimulated desorption processes and a decrease of secondary emission yields (SEY). To understand the role of the surface chemistry of air exposed materials in the electron conditioning process, typical air exposed materials used in particle accelerators : thin film coatings (NEG and TiN), copper (and its oxides Cu2O and CuO) and Niobium were conditioned by low energy electron irradiation for a better understanding of Ecloud effect. First, SEY was measured to understand the changes of surface conditioning upon particle irradiation; then, surface chemistry evolution after electron irradiation was investigated by both XPS and TOF-SIMS analyses using the ANDROMEDE facility at IJCLab. Finally, the relationship between the surface chemistry and the conditioning phenomenon will be discussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK029  
About • Received ※ 20 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 05 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK036 Determination of Pumping and Dynamic Vacuum Properties of Conductive Quaternary Alloy of TiZrVAg Non-Evaporable Getter. vacuum, photon, experiment, site 2843
 
  • R. Valizadeh, A.N. Hannah, O.B. Malyshev
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • G.Y. Hsiung
    NSRRC, Hsinchu, Taiwan
  • J.M. O’Callaghan Castella
    Universitat Politécnica de Catalunya, Barcelona, Spain
  • M. Pont, N.D. Tagdulang
    ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
 
  Non Evaporable Getter (NEG) coating has been employed extensively in the particle accelerator especially where the vacuum conductance of the vessel is severely restricted and ultra-high vacuum condition is required. NEG coating will significantly reduce the outgassing rate and provides active pumping surface for H2, CO and CO2. In addition, it has been proven that NEG coated surfaces have a very low secondary electron yield, as well as low photon and electron stimulated desorption yields. However, the existing NEG film increases the RF surface resistance of the beam pipe. In order to increase NEG coating conductivity, at ASTeC, in the past several years, the alternative NEG com-position have been studied by adding more conductive element such as Cu, Au, Al and Ag. In this study, we report on the photon stimulated desorption, activation temperature and surface resistance from room temperature to cryogenic temperature for a new NEG quaternary alloy of TiVZrAg as function of the film composition.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK036  
About • Received ※ 07 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK038 Electron Stimulated Desorption From Titanium Tube vacuum, radiation, photon, experiment 2850
 
  • O.B. Malyshev, R. Valizadeh
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
 
  Titanium is one of material that used for production of accelerator vacuum chamber and components. In this paper we report the results of vacuum properties evaluation measurements of titanium vacuum chamber. The sample was produced from 40-mm inner diameter tube made of titanium and equipped with CF40 flanges at both ends. The electron stimulated desorption (ESD) was measured after 24-h bakeout to 80, 150, 180 and 250 oC. H2 and CO initial sticking probabilities were measured after bakeout before the ESD measurements. After ESD measurements, the initial H2 and CO sticking probabilities were measured again together with CO sorption capacity. These measurements provide the results for ESD as a function of electron dose baked to different temperatures and demonstrate the efficiency of electron stimulated activation of titanium vacuum chamber.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK038  
About • Received ※ 25 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK041 Development of Programmable Bipolar Multi kHz Kicker Drivers for Long Pulse Superconducting Electron Linacs kicker, FEL, gun, laser 2862
 
  • J.L. Teichgräber, W. Decking, J. Kahl, F. Obier
    DESY, Hamburg, Germany
 
  Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany Superconducting cavities allow for long rf-pulses, which enable the acceleration of thousands of electron bunches within one rf-pulse. Due to transient effects, e.g. coupler kicks, eddy currents or wakefields, bunch properties like the beam trajectory can change along the pulse train. To compensate for this, kicker systems based on high-current operational amplifiers have been developed for the free electron lasers European XFEL and FLASH at DESY in Hamburg. Here, we present the layout of the kicker system, the setup of the pulse electronics, and operational results with beam.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK041  
About • Received ※ 03 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 19 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK042 Non-Linear Phenomena Studies in High-Gradient RF Technology for Hadrontherapy at IFIC cavity, radiation, accelerating-gradient, hadrontherapy 2865
 
  • P.M.R. Martinez-Reviriego, C. Blanch Gutiérrez, D. Esperante Pereira, J. Fuster, N. Fuster-Martínez, B. Gimeno, D. Gonzalez-Iglesias, P. Martín-Luna
    IFIC, Valencia, Spain
 
  High-Gradient accelerating cavities are one of the main research lines in the development of compact linear colliders. However, the operation of such cavities is currently limited by non-linear effects that are intensified at high electric fields, such as dark currents and radiation emission or RF breakdowns. A new normal-conducting High Gradient S-band Backward Travelling Wave accelerating cavity for medical application (v=0.38c) designed and constructed at CERN is being tested at IFIC. In this paper, we present experimental measurements and simulation of such non-linear effects. The main goal of these studies is to establish the viability of using these techniques in linear accelerators, in order to improve our understanding in such effects. The main goal of these studies is to determine the viability of using this techniques in linear accelerators for hadrontherapy treatments in hospitals.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK042  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK048 Radiation Load Studies for the FCC-ee Positron Source with a Superconducting Matching Device target, positron, collider, shielding 2879
 
  • B. Humann
    TU Vienna, Wien, Austria
  • B. Auchmann, J. Kosse
    PSI, Villigen PSI, Switzerland
  • I. Chaikovska, S. Ogur
    Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
  • B. Humann, A. Latina, A. Lechner, Y. Zhao
    CERN, Meyrin, Switzerland
 
  For an electron-positron collider like FCC-ee, the production of positrons plays a crucial role. One of the design options considered for the FCC-ee positron source employs a superconducting solenoid made of HTS coils as an adiabatic matching device. The solenoid, which is placed around the production target, is needed to capture positrons before they can be accelerated in a linear accelerator. A superconducting solenoid yields a higher peak field than a conventional-normal conducting magnetic flux concentrator, therefore increasing the achievable positron yield. In order to achieve an acceptable positron production, the considered target is made of tungsten-rhenium, which gives also a significant flux of un-wanted secondary particles, that in turn could generate a too large radiation load on the superconducting coils. In this study, we assess the feasibility of such a positron source by studying the heat load and long-term radiation damage in the superconducting matching device and surrounding structures. Results are presented for different geometric configurations of the superconducting matching device.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK048  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 07 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK054 Proposal of a VHEE Linac for FLASH Radiotherapy linac, cavity, gun, simulation 2903
 
  • L. Giuliano, F. Bosco, M. Carillo, D. De Arcangelis, A. De Gregorio, L. Ficcadenti, D. Francescone, G. Franciosini, M. Migliorati, A. Mostacci, L. Palumbo, V. Patera, A. Sarti
    Sapienza University of Rome, Rome, Italy
  • D. Alesini, A. Gallo, A. Vannozzi
    INFN/LNF, Frascati, Italy
  • M. Behtouei, L. Faillace, B. Spataro
    LNF-INFN, Frascati, Italy
  • M.G. Bisogni, F. Di Martino, J.H. Pensavalle
    INFN-Pisa, Pisa, Italy
  • G.A.P. Cirrone, G. Cuttone, G. Torrisi
    INFN/LNS, Catania, Italy
  • V. Favaudon, A. Patriarca
    Institut Curie - Centre de Protonthérapie d’Orsay, Orsay, France
  • S. Heinrich
    Institut Curie, Centre de Recherche, Orsay, France
 
  Translation of electron FLASH radiotherapy in clinical practice requires the use of high energy accelerators to treat deep tumours and Very High Electron Energy (VHEE) could represent a valid technique to achieve this goal. In this sce- nario, a VHEE FLASH linac is under study at the University La Sapienza of Rome (Italy) in collaboration with the Italian Institute for Nuclear Research (INFN) and the Curie Insti- tute (France). Here we present the preliminary results of a compact C-band system aiming to reach an high accelerating gradient and an high pulse current necessary to deliver high dose per pulse and ultra-high dose rate required for FLASH effect. We propose a system composed of a low energy high current injector linac followed by a modular section of high accelerating gradient structures. CST code is used to define the required LINAC’s RF parameters and beam dynamics simulations are performed using T-Step, ASTRA and GPT tracking codes.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK054  
About • Received ※ 17 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK059 Laser System for SuperKEKB RF Gun in Phase III Commissioning laser, MMI, injection, gun 2914
 
  • R. Zhang, M. Yoshida, X. Zhou
    KEK, Ibaraki, Japan
  • H.K. Kumano, N. Toyotomi
    Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan
 
  In order to generate high quality electron beam with high charge in Phase III commissioning of SuperKEKB, some improvements have been done in Ytterbium doped fiber and Neodymium doped YAG (Nd:YAG) hybrid laser system. Spatial reshaping part for the 4th harmonic laser beam at 266 nm has been adopted to realize low emittance electron beam. In addition, for achieving continuous and stable laser operation, position feedback system has also been used to improve the pointing stability of laser beam. In 2021 commissioning of SuperKEKB, stable 2 nC electron beam is generated for high energy ring (HER) injection. Meanwhile, we achieved the best emittance results at B-sector of linac injector and BT line for comparable low injection background and higher injection efficiency. With the aim of generating higher charge electron beam with good quality in the following commissioning, a perspective towards the next step update for current laser system is also introduced.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK059  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOTK061 Machine Learning Approach to Temporal Pulse Shaping for the Photoinjector Laser at CLARA laser, network, target, experiment 2917
 
  • A.E. Pollard, D.J. Dunning, W.A. Okell, E.W. Snedden
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
 
  The temporal profile of the electron bunch is of critical importance in accelerator areas such as free-electron lasers and novel acceleration. In FELs, it strongly influences factors including efficiency and the profile of the photon pulse generated for user experiments, while in novel acceleration techniques it contributes to enhanced interaction of the witness beam with the driving electric field. Work is in progress at the CLARA facility at Daresbury Laboratory on temporal shaping of the ultraviolet photoinjector laser, using a fused-silica acousto-optic modulator. Generating a user-defined (programmable) time-domain target profile requires finding the corresponding spectral phase configuration of the shaper; this is a non-trivial problem for complex pulse shapes. Physically informed machine learning models have shown great promise in learning complex relationships in physical systems, and so we apply machine learning techniques here to learn the relationships between the spectral phase and the target temporal intensity profiles. Our machine learning model extends the range of available photoinjector laser pulse shapes by allowing users to achieve physically realisable configurations for arbitrary temporal pulse shapes.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK061  
About • Received ※ 30 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 01 July 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS008 Physics Design of Electron Flash Radiation Therapy Bemaline at PITZ radiation, quadrupole, simulation, booster 2954
 
  • X.-K. Li, Z. Aboulbanine, Z. Amirkhanyan, M. Groß, M. Krasilnikov, A. Lueangaramwong, R. Niemczyk, A. Oppelt, S. Philipp, H.J. Qian, F. Stephan
    DESY Zeuthen, Zeuthen, Germany
  • G. Loisch, F. Obier, M. Schmitz
    DESY, Hamburg, Germany
 
  The Photo Injector Test facility at DESY in Zeuthen (PITZ) is preparing an R&D platform for electron FLASH radiotherapy, very high energy electron (VHEE) radiotherapy and radiation biology based on its unique beam parameters: ps scale bunches with up to 5 nC bunch charge at MHz bunch repetition rate in bunch trains of up to 1 ms in length repeating at 10 Hz. This platform is called FLASHlab@PITZ. The PITZ beam is routinely accelerated to 22 MeV, with a possible upgrade to 250 MeV for VHEE radiotherapy in the future. The 22 MeV beam will be used for dosimetry experiments and studying biological effects in thin samples in the next years. A new beamline to extract and match the beam to the experimental station is under physics design. The main features include: an achromatic dogleg to extract the beam from the PITZ beamline; a sweeper to scan the beam across the sample within 1 ms for tumor painting studies; and an imaging system to keep the beam size small at the sample after scattering in the exit window while maintaining the scan range of the sweeper. In this paper, the beam dynamics with bunch charges from 10 pC to 5 nC in and the preparation of the new beamline will be presented.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS008  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS010 Heating and Beam Impact of High Intensity Exit Windows for FLASHlab@PITZ radiation, scattering, Windows, simulation 2958
 
  • Z. Amirkhanyan
    CANDLE SRI, Yerevan, Armenia
  • Z. Aboulbanine, M. Groß, M. Krasilnikov, T. Kuhl, X.-K. Li, R. Niemczyk, A. Oppelt, S. Philipp, H.J. Qian, F. Stephan
    DESY Zeuthen, Zeuthen, Germany
  • M. Schmitz
    DESY, Hamburg, Germany
 
  The high-brightness electron beam at the Photo Injector Test facility at DESY in Zeuthen (PITZ) is being prepared for use in dosimetry experiments and for the study of biological effects in thin samples. This is part of the preparations for FLASHlab@PITZ which is going to be an R&D platform for FLASH and VHEE radiation therapy and radiation biology. These studies require precise information on the electron beam parameters downstream of the exit window, such as the scattering angle and the energy spectrum of the particles as well as the thermal load on the exit window. A Titanium window is compared with a DESY Graphite window design. Heat deposition in the window by a single 22MeV / 1nC electron bunch of various size, its scattering and energy spectrum due to passage through the window are calculated by means of the Monte Carlo program FLUKA. Time resolved temperature profiles, as generated by the passage of 1ms long electron pulse trains with up to 4500 single pulses, each of them between 0.1 and 60ps long, are calculated with a self-written FEM code.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS010  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS013 Electron Gun System Design for FLASH Radiotherapy gun, cathode, power-supply, radiation 2970
 
  • H.-S. Lee, J.H. Jang, K.Y. Jang, J.C. Koo, H.S. Shin, D.H. Yu
    VITZRONEXTECH, Ansan-si, Gyeonggi-do, Republic of Korea
  • D.H. An, S.H. Choi, K.U. Kang, G.B. Kim, J.H. Kim
    KIRAMS, Seoul, Republic of Korea
  • Y.G. Son
    PAL, Pohang, Republic of Korea
 
  An electron gun is a device that emits electron beams used in an electron accelerator, an electron beam welder, an x-ray generator, etc. This device can be broadly divided into three components: a cathode, a grid, and an anode. A medical electron gun, which is a sub-system of an electron accelerator for FLASH radiotherapy, requires a high current. The electron gun was designed to obtain a peak current up to 15A using EIMAC Y824 cathode. We would like to introduce the structure of the electron gun and the required power supply system. In this paper, we will describe the optimization process of the electron gun structure design, the Marx-type power supply providing 200 kV pulse voltage, and the grid pulse power supply ranging from 1ns to 1.5 ’s.
Electron gun design, Accelerator, Radiotherapy, High Current
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS013  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 28 June 2022 — Issue date ※ 10 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS020 Beam Optics Study for a Potential VHEE Beam Delivery System scattering, optics, quadrupole, dipole 2992
 
  • C.S. Robertson, P. Burrows
    JAI, Oxford, United Kingdom
  • M. Dosanjh, A. Gerbershagen, A. Latina
    CERN, Meyrin, Switzerland
 
  VHEE (Very High Energy Electron) therapy can be superior to conventional radiotherapy for the treatment of deep seated tumours, whilst not necessarily requiring the space and cost of proton or heavy ion facilities. Developments in high gradient RF technology have allowed electrons to be accelerated to VHEE energies in a compact space, meaning that treatment could be possible with a shorter linac. A crucial component of VHEE treatment is the transfer of the beam from accelerator to patient. This is required to magnify the beam to cover the transverse extent of the tumour, whilst ensuring a uniform beam distribution. Two principle methodologies for the design of a compact transfer line are presented. The first of these is based upon a quadrupole lattice and optical magnification of beam size. A minimisation algorithm is used to enforce certain criteria on the beam distribution at the patient, defining the lattice through an automated routine. Separately, a dual scattering-foil based system is also presented, which uses similar algorithms for the optimisation of the foil geometry in order to achieve the desired beam shape at the patient location.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS020  
About • Received ※ 19 May 2022 — Accepted ※ 16 June 2022 — Issue date ※ 18 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS026 Monte Carlo Simulation of Electron Beam in Phantom Water for Radiotherapy Application simulation, radiation, photon, linac 3011
 
  • P. Apiwattanakul, C. Phueng-ngern, S. Rimjaem, J. Saisut
    Chiang Mai University, Chiang Mai, Thailand
  • P. Lithanatudom
    IST, Chiang Mai, Thailand
  • P. Nimmanpipug, S. Rimjaem, J. Saisut
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  Radiotherapy (RT) is an effective treatment that can control the growth of cancer cells. There is a hypothesis suggests that secondary electrons with an energy of a few eV produced from RT play an important role on cancer’s DNA strand break. In this study, the Monte Carlo simulation of electron beam irradiation in phantom water is performed to investigate the production of low-energy electrons. Electron beams produced from an radio-frequency linear accelerator (RF linac) are used in this study. The accelerator can generate the electron beam with adjustable energy of up to 4 MeV and adjustable repetition rate of up to 200 Hz. With these properties, the electron dose can be varied. We used ASTRA software to simulate the electron beam dynamics in the accelerator and GEANT4 toolkit for studying interactions of electrons in water. The energy of electrons decreases from MeV scale to keV-eV scale as they travel in the water. From simulations, the dose distribution and depth in phantom water were obtained for the electron dose of 1, 3, 5, 10, 25, and 50 Gy. Further study on effect of low-energy electron beam with these dose values on cancer DNAs will be performed with GEANT4-DNA simulation.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS026  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 25 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS029 Testing the Properties of Beam-Dose Monitors for VHEE-FLASH Radiation Therapy detector, radiation, experiment, real-time 3018
 
  • J.J. Bateman, P. Burrows, L.A. Dyks
    JAI, Oxford, United Kingdom
  • R. Corsini, M. Dosanjh, W. Farabolini, A. Gerbershagen, N. Heracleous, P. Korysko, S. Morales Vigo, V. Rieker, B. Salvachúa, M. Silari, G. Zorloni
    CERN, Meyrin, Switzerland
  • F. Murtas
    LNF-INFN, Frascati, Italy
 
  Very High Energy Electrons (VHEE) of 50 - 250 MeV are an attractive choice for FLASH radiation therapy (RT). Before VHEE-FLASH RT can be considered for clinical use, a reliable dosimetric and beam monitoring system needs to be developed, able to measure the dose delivered to the patient in real-time and cut off the beam in the event of a machine fault to prevent overdosing the patient. Ionisation chambers are the standard monitors in conventional RT; however, their response saturates at the high dose rates required for FLASH. Therefore, a new dosimetry method is needed that can provide reliable measurements of the delivered dose in these conditions. Experiments using 200 MeV electrons were done at the CLEAR facility at CERN to investigate the properties of detectors such as diamond beam loss detectors, GEM foil detectors, and Timepix3 ASIC chips. From the tests, the GEM foil proved to be the most promising.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS029  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS030 Updates, Status and Experiments of CLEAR, the CERN Linear Electron Accelerator for Research experiment, radiation, plasma, focusing 3022
 
  • P. Korysko
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
  • J.J. Bateman, C.S. Robertson
    JAI, Oxford, United Kingdom
  • R. Corsini, M. Dosanjh, L.A. Dyks, A. Gilardi, V. Rieker
    CERN, Meyrin, Switzerland
  • W. Farabolini
    CEA-DRF-IRFU, France
  • K.N. Sjobak
    University of Oslo, Oslo, Norway
 
  The CERN Linear Accelerator for Research (CLEAR) at CERN is a test facility using a 200 MeV electron beam. In 2020 and 2021, a few hardware upgrades were done: comparators for position measurements were added on components, the in-air experimental area was re-arranged in order to provide more space, a robotic system was built to enable remote samples manipulations for irradiation studies, the BPM reading system was optimized and the laser double-bunch system implemented to allow for a doubling of the electron bunch frequency from 1.5 GHz to 3 GHz. In the paper, we describe such improvements, we outline the experimental activities during 2021 and illustrate the diverse program for the next 4 years, including high doses’ irradiation studies for medical applications.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS030  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS031 VHEE High Dose Rate Dosimetry Studies in CLEAR radiation, GUI, real-time, status 3026
 
  • V. Rieker, R. Corsini, L.A. Dyks
    CERN, Meyrin, Switzerland
  • J.J. Bateman
    JAI, Oxford, United Kingdom
  • W. Farabolini
    CEA-DRF-IRFU, France
  • P. Korysko
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
 
  The 200 MeV electron beam of the CERN Linear Accelerator for Research (CLEAR) user facility at CERN has been intensively used to study the potential use of Very High Energy Electrons (VHEE) in cancer radiotherapy. In particular, irradiation tests have been performed in the high dose rate regime, which has gained a lot of interest for the so called FLASH biological effect, in which cancer cells are damaged while healthy tissue is largely spared. High dose rate dosimetry, though, poses a number of challenges: to validate standard or new methods of passive dosimetry, like radiochromic films and alanine pellets, and especially to develop new methods for real-time dosimetry since the normally used ionization chambers suffer from non-linear effects at high dose rates. In this paper we describe the results of experimental activities at CLEAR aimed at developing solid, high-dose rate dosimetry standards adapted to VHEE beams.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS031  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 06 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS033 Design and Optimisation of a Stationary Chest Tomosynthesis System with Multiple Flat Panel Field Emitter Arrays: Monte Carlo Simulations and Computer Aided Designs photon, simulation, target, diagnostics 3034
 
  • T.G. Primidis, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • T.G. Primidis, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • T.G. Primidis
    King’s College London, London, United Kingdom
  • V. Soloviev, S.G. Wells
    Adaptix Ltd, Oxford, United Kingdom
 
  Funding: Funded by the Accelerators for Security, Healthcare and Environment Centre for Doctoral Training of the United Kingdom Research and Innovation, Science and Technology Facilities Council, ST/R002142/1
Digital tomosynthesis (DT) allows 3D imaging by using a ~30° range of projections instead of a full circle as in computed tomography (CT). Patient doses can be ~10 times lower than CT and similar to 2D radiography but diagnostic ability is significantly better than 2D radiography and can approach that of CT. Moreover, cold-cathode field emission technology allows the integration of 10s of X-ray sources into source arrays that are smaller and lighter than conventional X-ray tubes. The distributed source positions avoid the need for source movements and Adaptix Ltd has demonstrated stationary 3D imaging with this technology in dentistry, orthopaedics, veterinary medicine and non-destructive testing. In this work we present Monte Carlo simulations of an upgrade to the Adaptix technology to specifications suited for chest DT and we show computer aided designs for a system with various populations of these source arrays. We conclude that stationary arrays of cold-cathode X-ray sources could replace movable X-ray tubes for 3D imaging and different arrangements of many such arrays could be used to tailor the X-ray fields to different patient size and diagnostic objective.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS033  
About • Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS036 HERACLES: A High Average Current Electron Beamline for Lifetime Testing of Novel Photocathodes cathode, gun, vacuum, laser 3041
 
  • M.B. Andorf, J. Bae, A.C. Bartnik, I.V. Bazarov, J.M. Maxson
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • L. Cultrera
    BNL, Upton, New York, USA
 
  Funding: DOE-NP DE-SC0021425 NSF PHY 1549132
We report on the building and commissioning of a high current beamline dedicated to testing novel photocathodes for high current and spin-polarized electron applications. The main features of the beamline are a 200 keV DC electron gun and a beam dump capable of handling 75 kW of beam power. In this report, a Cs3Sb photocathode is used to demonstrate the facilities high current capabilities.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS036  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS039 Investigation on Intermolecular Interactions in Ionic Liquids Using Accelerator-based THz Transition Radiation experiment, radiation, FEM, ion-source 3053
 
  • P. Nanthanasit, S. Rimjaem
    Chiang Mai University, Chiang Mai, Thailand
  • N. Chattrapiban, P. Nimmanpipug, S. Rimjaem
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
  • M. Jitvisate
    Suranaree University of Technology, Nakhon Ratchasima, Thailand
 
  Ionic liquids (ILs) are interesting material that can be used in many applications. Spectroscopic measurement using accelerator-based terahertz transition radiation (THz TR) is one of potential techniques to investigate their intermolecular interactions by observing the vibra-tional bands in the terahertz region due to TR’s excep-tional properties: coherent, broadband, and high intensi-ty. This work aims to study intermolecular interactions of ILs using the THz TR produced from an electron beam at the PBP-CMU Electron Linac Laboratory. The THz TR with the frequency range of 0.3-2.5 THz can be produced from electron beam of energy 10-25 MeV. This radiation is produced and transported to the experimental area, where it is used as the coherent and polarization selective light source for the Fourier transform infrared (FTIR) spectrometer. The absorption spectrum in the THz region of the ILs is then measured. In addition, to explain the experimental results deeply, theoretical calculations using the density functional theory are performed. In this contribution, we present the results from experiment and computational calculation that can be used together to describe the intermolecular interactions in ILs.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS039  
About • Received ※ 08 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 02 July 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS040 Present Status of Linear Accelerator System for Natural Rubber Vulcanization at Chiang Mai University radiation, experiment, linac, shielding 3057
 
  • C. Thongbai, P. Jaikaew, E. Kongmon, S. Rimjaem, J. Saisut, P. Wongkummoon
    Chiang Mai University, Chiang Mai, Thailand
  • N. Khangrang
    Chiang Mai University, PBP Research Facility, Chiang Mai, Thailand
  • M.W. Rhodes, S. Rimjaem, J. Saisut, C. Thongbai
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  At the Plasma and Beam Physics (PBP) Research Fa-cility, Chiang Mai University (CMU), an electron beam accelerator system for natural rubber irradiation has been under development and is currently under the commissioning. The research project is carried out with the aim to modify an old medical linac, retired from the clinical operation, for rubber latex vulcanization and materials irradiation using electron beams. The accelerator system consists of a DC-thermionic cathode electron gun, a standing-wave RF linear accelerator, an RF system, a control system, beam diagnostic systems, and an irradia-tion system. The components were completely assembled, and the RF system was tested. The RF processing has been performed and some of the electron beam properties have been measured. This contribution presents some experimental results while developing and testing the various sub-systems of this accelerator. The present status of development and some vulcanization results will also be reported in this contribution.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS040  
About • Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 04 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS041 Design and Parameterization of Electron Beam Irradiation System for Natural Rubber Vulcanization experiment, simulation, radiation, linac 3061
 
  • P. Wongkummoon
    Chiang Mai University, PBP Research Facility, Chiang Mai, Thailand
  • N. Kangrang, S. Rimjaem, J. Saisut, C. Thongbai
    Chiang Mai University, Chiang Mai, Thailand
  • M.W. Rhodes
    IST, Chiang Mai, Thailand
 
  Electron beam irradiation is a process to modify or improve the properties of materials with less chemical residue. In natural rubber vulcanization, a proper electron absorbed dose is about 50-150 kGy. In this study, the experimental station is designed to investigate the deposition of the electron beam in natural rubber. Electron beams generated from an RF linac are used in this study. This accelerator can generate the beam with energies in the range of 1-4 MeV and an adjustable repetition rate of up to 200 Hz. We can optimize these parameters to maximize the throughput and uniformity of electron dose in the vulcanization. The simulation results from GEANT4 were used to narrow down the appropriate parameters in the experiment. In the early stage of the study, water was used as a sample instead of natural rubber. The dose distribution was obtained by placing a B3 film dosimeter under a water chamber. The water depth was varied from 0.5 to 2.0 cm. The simulation results provide the dose distribution to compare with the experimental results. In a further study, the beam irradiation in natural rubber with these optimal parameters and vulcanization tests will be performed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS041  
About • Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS046 Generation of Flat-Laser Compton Scattering Gamma-ray Beam in UVSOR undulator, laser, simulation, experiment 3070
 
  • H. Ohgaki, K. Ali, T. Kii, H. Zen
    Kyoto University, Kyoto, Japan
  • M. Fujimoto, Y. Taira
    UVSOR, Okazaki, Japan
  • T. Hayakawa, T. Shizuma
    QST, Tokai, Japan
 
  Funding: This work is supported by JSPS KAKENHI Grant Number 21H01859. A part of this work was performed at the BL1U of UVSOR, IMS, Okazaki (IMS program 21-603).
Flat energy distribution Laser Compton scattering (F-LCS) gamma-ray beam, which has a flat distribution in the energy spectrum and the spatial distribution with a small beam size, has been developed to study an isotope selective CT Imaging application at the beamline BL1U in UVSOR. We have successfully demonstrated a three-dimensional (3D) isotope-selective CT image by using a conventional LCS gamma-ray beam[1]. However, the conventional LCS beam with a small beam size whose energy spread is narrow can’t excite a few isotopes at the same time. Therefore, we proposed the F-LCS gamma-ray beam by using the Apple-II undulator installed in BL1U in UVSOR to excite a circular motion of the electron beam. An EGS5 simulation shows that a weak magnetic field (K=0.2) can generate an F-LCS beam. The demonstration experiments have been carried out in UVSOR and the spectra of generated LCS beam with different K-values of the undulator were measured. As a result, the measured spectra agreed with the EGS5 simulation. The principle of F-LCS generation and experimental results, including the effect on the stored electron beam, will be presented at the conference.
[1] K. Ali, et. al., "Three-dimensional nondestructive isotope-selective tomographic imaging of 208Pb distribution via nuclear resonance fluorescence". Appl. Sci. 2021, 11, 3415.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS046  
About • Received ※ 02 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS047 Design of Radiation Shielding for the PBP-CMU Electron Linac Laboratory radiation, shielding, photon, neutron 3073
 
  • P. Jaikaew, N. Khangrang
    Chiang Mai University, PBP Research Facility, Chiang Mai, Thailand
  • M. Jitvisate
    Suranaree University of Technology, Nakhon Ratchasima, Thailand
  • S. Rimjaem
    Chiang Mai University, Chiang Mai, Thailand
  • S. Rimjaem
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
 
  The local radiation shielding is designed for the electron linear accelerator beam dump at the PBP-CMU Electron Linac Laboratory (PCELL) with the aim to control the annual ambient dose equivalent during the operation. The study of radiation generation and design of radiation shielding is conducted based on the Monte Carlo simulation toolkit GEANT4. The study results include an annual ambient dose equivalent map and design of local shielding for the first bam dump downstream the linac section. With this design, the leaking radiation outside the accelerator hall is completely blocked and the average annual ambient dose equivalent on the rooftop of the hall is within the IAEA safety limit for the supervised area. The shielding model will then be used as a guideline for the construction in the near future.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS047  
About • Received ※ 07 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 15 June 2022  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS050 Design of Linac Based Neutron Source neutron, target, photon, linac 3084
 
  • N. Upadhyay, S. Chacko
    University of Mumbai, Mumbai, India
  • A.P. Deshpande, T.S. Dixit, R. Krishnan
    SAMEER, Mumbai, India
 
  Neutron sources are of great utility for various applications, especially in the fields of nuclear medicine, nuclear energy and imaging. At SAMEER, we have designed a linear electron accelerator based neutron source via photo-neutron generation. The accelerator is a 15 MeV linac with both photon and electron mode and is capable of delivering high beam current to achieve beam power of 1 to 2 kW. Efforts are in place to achieve further higher beam powers. 15 MeV electrons are incident on a bremsstrahlung target followed by a secondary target to achieve neutrons. To further optimize and enhance the neutron yield, backing material is provided. In this paper, we present the simulation of (e, g) and (g, n) processes using the Monte Carlo code FLUKA. The optimization of Tungsten as the convertor target whereas of the Beryllium as the neutron target is discussed in detail. We have explored various backing materials in order to optimize the total neutron yield as well as the thermal neutron yield. The simulation results have been considered for the finalisation of all material parameters for the set-up of this neutron source activity.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS050  
About • Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 14 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOMS056 An Overview of the Applications of MIR and THz Spectroscopy in Astrochemistry Studies experiment, detector, FEL, radiation 3102
 
  • C. Suwannajak, U. Keyen, A. Leckngam, N. Tanakul
    NARIT, Chiang Mai, Thailand
  • W. Jaikla, S. Pakluea, P. Wongkummoon
    Chiang Mai University, PBP Research Facility, Chiang Mai, Thailand
  • M. Jitvisate
    Suranaree University of Technology, Nakhon Ratchasima, Thailand
  • P. Nimmanpipug, S. Rimjaem
    ThEP Center, Commission on Higher Education, Bangkok, Thailand
  • S. Pakluea, S. Rimjaem, P. Wongkummoon
    Chiang Mai University, Chiang Mai, Thailand
  • T. Phimsen
    SLRI, Nakhon Ratchasima, Thailand
 
  Interstellar complex molecules can be found in molecular clouds which are spread throughout our galaxy. Some of these molecules are thought to be the precursors of bio-molecules. Therefore, understanding the formation processes of those interstellar complex molecules is crucial to understanding the origin of the building blocks of life. There are currently more than a hundred known complex molecules discovered in interstellar clouds. However, the formation processes of those molecules are not yet well understood since they occur in very extreme conditions and very short time scale. Ultrafast spectroscopy can be applied to study those processes that occur in the time scale of femtoseconds or picoseconds. In this work, we present an overview of the applications of MIR and THz pump-probe experiments in astrochemistry studies. An experimental setup to simulate space conditions that mimic the environments where the interstellar complex molecules are formed is currently being developed at the PBP-CMU Electron Linac Laboratory. Then, we present our development plan of the experimental station and its current status.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS056  
About • Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FROXGD1 A Method for Obtaining 3D Charge Density Distribution of a Self-Modulated Proton Bunch proton, plasma, experiment, wakefield 3118
 
  • T. Nechaeva, P. Muggli
    MPI-P, München, Germany
  • L. Verra, G. Zevi Della Porta
    CERN, Meyrin, Switzerland
  • L. Verra
    TUM, Munich, Germany
  • L. Verra
    MPI, Muenchen, Germany
 
  The Advanced Wakefield Experiment (AWAKE) at CERN is the first plasma wakefield accelerator experiment to use a proton bunch as driver. The long bunch undergoes seeded self-modulation (SSM) in a 10 m-long plasma. SSM transforms the bunch into a train of short micro-bunches that resonantly drive high-amplitude wakefields. We use optical transition radiation (OTR) and a streak camera to obtain time-resolved images of the bunch transverse charge density distribution in a given plane. In this paper we present a method to obtain 3D images of the bunch by scanning the OTR across the entrance slit of the streak camera. Reconstruction of the 3D distribution is possible because with seeding self-modulation is reproducible*. The 3D images allow for checking the axi-symmetry of SSM and for detecting the possible presence of the non-axi-symmetric hosing instability (HI).
* F. Batsch et al., Phys. Rev. Lett. 126, 164802 (2021).
 
slides icon Slides FROXGD1 [4.026 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXGD1  
About • Received ※ 20 May 2022 — Revised ※ 15 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FROXGD3 Injection Beam Measurement Using Synchrotron Radiation Monitor at the SuperKEKB Electron Ring injection, extraction, synchrotron, operation 3121
 
  • H. Ikeda, T.M. Mitsuhashi, G. Mitsuka
    KEK, Ibaraki, Japan
 
  We upgraded the diamond mirror of the SuperKEKB electron ring to extract the good quality synchrotron light in 2020 summer. As a result, the accuracy of profile measurement for each bunch using a gate camera has improved dramatically, and it has become possible to measure the incident beam for each turn. The electron beam was injected with single turn injection mode to measure the properties of the beam and measured turn by turn after injection. In order to convert the measurement results into beam size, convolution by diffraction effect and absolute value calibration using real images were performed. We report the behavior of the injection beam during normal operation of SuperKEKB.  
slides icon Slides FROXGD3 [5.560 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXGD3  
About • Received ※ 09 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 07 July 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FRIXSP1 Low-Emittance Compact RF Electron Gun with a Gridded Thermionic Cathode gun, emittance, cathode, cavity 3124
 
  • T. Asaka
    JASRI/SPring-8, Hyogo-ken, Japan
 
  A new type of rf electron gun has been developed to generate a stable electron beam with a low-emittance of ~1 um.rad, that can be injected into SX-FEL and DLSR, without using a large UV laser system nor an ultra-high voltage pulsers. This electron gun consists of a 50 kV pulsed gun equipped with a commercially available thermionic cathode with grid and a 238-MHz acceleration cavity driven by a 42 kW solid-state amplifier. The system is simple, stable, robust, and of easy-maintenance. To obtain a "grid-transparent" condition, the cathode voltage and the control grid voltage are optimized not to distort the electric field near the grid. To avoid the emittance growth due to the space charge effect, the gun and a special magnetic lens are embedded in the 238-MHz cavity at the shortest distance, and the beam energy is immediately accelerated to 500 kV. The first model of this electron gun has been operated as the 1 GeV injector of the NewSUBARU storage ring. The same electron gun will also be used in the injector linac of the 3 GeV light source under construction in Japan. The talk is expected to include the concept, overall design and the achieved performance.  
slides icon Slides FRIXSP1 [2.893 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FRIXSP1  
About • Received ※ 08 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 19 June 2022 — Issue date ※ 23 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FROXSP2 Demonstration of Gradient Above 300 MV/m in Short Pulse Regime Using an X-Band Single-Cell Structure acceleration, experiment, accelerating-gradient, wakefield 3134
 
  • J.H. Shao, D.S. Doran, G. Ha, C.-J. Jing, W. Liu, J.G. Power, C. Whiteford, E.E. Wisniewski
    ANL, Lemont, Illinois, USA
  • H.B. Chen, X. Lin, M.M. Peng, J. Shi, H. Zha
    TUB, Beijing, People’s Republic of China
  • C. Jing
    Euclid Beamlabs, Bolingbrook, USA
 
  High gradient acceleration is one of the critical technologies required by future linear colliders, free-electron lasers, and compact linac-based applications. Among decade long effort to break state-of-the-art gradient limitation of ~100 MV/m in normal conducting structures, using RF pulses shorter than 20 ns is a promising approach based on theoretic analysis and experimental observation. In this study, we demonstrated high gradient above 300 MV/m using an X-band 11.7 GHz single-cell travelling-wave structure with 6 ns FWHM RF pulses generated by a power extractor. In comparison, a scaled 11.424 GHz structure only reached below 150 MV/m driven by 30-100 ns RF pulses from a klystron with pulse compression. The experimental results and the suggested new mechanism of beam acceleration in the Breakdown Insensitive Acceleration Regime (BIAR) are presented in this manuscript.  
slides icon Slides FROXSP2 [8.998 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXSP2  
About • Received ※ 11 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
FRPLYGD2 Access to Effective Cancer Care in Low- Middle Income Countries Requires Sophisticated Linear Accelerator Based Radiotherapy linac, radiation, gun, survey 3147
 
  • M. Dosanjh
    CERN, Meyrin, Switzerland
 
  There are substantial and growing gaps in cancer care for millions of people in Low- Middle- Income countries (LMICs) and for geographically remote settings in High-income countries (HICs), often indigenous populations. Assessing the cancer care shortfall led to understanding the essential gap, that of a radiation therapy machine that can reliably and effectively provide the appropriate first-rate cancer treatments within the challenging environments. More than 10,000 electron linear accelerators (linacs) are currently used worldwide to treat patients. However only 10% of patients in low-income and 40% in middle-income countries who need radiotherapy have access to it. The idea to address the need for a novel medical linac for challenging environments has led to the creation of the STELLA project (Smart Technology to Extend Lives with Linear Accelerators) project. STELLA is multidisciplinary international collaborative effort to design and develop an affordable and robust yet technically sophisticated linear accelerator-based radiation therapy treatment (RTT) in LMICs. Here we describe Project STELLA.  
slides icon Slides FRPLYGD2 [6.047 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FRPLYGD2  
About • Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 29 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)