Keyword: FEL
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MOPLXGD2 Progress Towards Demonstration of a Plasma-Based FEL plasma, laser, electron, 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
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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, wakefield, electron, 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  
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MOPOPT020 Longitudinal Phase Space Diagnostics with Corrugated Structure at the European XFEL electron, diagnostics, 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
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MOPOPT026 Beam Diagnostics for the Storage Ring of the cSTART Project at KIT diagnostics, storage-ring, beam-diagnostic, electron 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
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MOPOPT029 Longitudinal Phase Space Benchmarking for PITZ Bunch Compressor simulation, booster, laser, experiment 310
 
  • A. Lueangaramwong, Z. Aboulbanine, G.D. Adhikari, N. Aftab, P. Boonpornprasert, G.Z. Georgiev, J. Good, M. Groß, C. Koschitzki, M. Krasilnikov, X.-K. Li, O. Lishilin, D. Melkumyan, H.J. Qian, G. Shu, F. Stephan, G. Vashchenko, T. Weilbach
    DESY Zeuthen, Zeuthen, Germany
  • N. Chaisueb
    Chiang Mai University, Chiang Mai, Thailand
  
  The longitudinal phase space characteristics of space-charge dominated electron beams are keys to achieving bunch compression for the accelerator-based THz source at the Photo Injector Test facility at DESY in Zeuthen (PITZ). Such a THz source is proposed as a prototype for an accelerator-based THz source for pump-probe experiments at the European XFEL. A start-to-end simulation has suggested the settings of the phase of booster linear accelerator manipulating longitudinal beam characteristics to optimize the performance of the THz FEL. Although beam diagnostics after compression at PITZ are limited, the longitudinal beam characteristics as a function of the booster phase have been measured and compared with the corresponding simulations. The benchmark involves measurements of longitudinal phase space distribution for bunch charges up to 2 nC. The measurement technique assigned uses 50-um slits to achieve higher momentum and time resolution (1.8 keV/c and 0.5 ps, respectively).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT029  
About • Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 18 June 2022
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MOPOPT049 Study on Energy Spectrum Measurement of Electron Beam for Producing MIR-FEL at PBP-CMU Electron Linac Laboratory electron, dipole, 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
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MOPOPT069 A Data-Driven Beam Trajectory Monitoring at the European XFEL lattice, undulator, experiment, operation 418
 
  • A. Sulc, R. Kammering, T. Wilksen
    DESY, Hamburg, Germany
  
  Funding: This work was supported by HamburgX grant LFF-HHX-03 to the Center for Data and Computing in Natural Sciences (CDCS) from the Hamburg Ministry of Science, Research, Equalities and Districts.
Interpretation of data from beam position monitors is a crucial part of the reliable operation of European XFEL. The interpretation of beam positions is often handled by a physical model, which can be prone to modeling errors or can lead to the high complexity of the computational model. In this paper, we show two data-driven approaches that provide insights into the operation of the SASE beamlines at European XFEL. We handle the analysis as a data-driven problem, separate it from physical peculiarities and experiment with available data based only on our empirical evidence and the data. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT069  
About • Received ※ 06 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022  
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MOPOTK013 Machine Learning Based Surrogate Model Construction for Optics Matching at the European XFEL optics, simulation, quadrupole, electron 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
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MOPOMS023 Start-to-End Beam-Dynamics Simulations of a Compact C-Band Electron Beam Source for High Spectral Brilliance Applications electron, simulation, 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
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MOPOMS027 Synthesis of First Caesium Telluride Photocathode at ASTeC Using Sequential and Co-Deposition Method cathode, target, site, electron 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
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MOPOMS029 HPC Modeling of a High-Gradient C-Band Linac for Hard X-Ray Free-Electron Lasers simulation, cavity, electron, 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  
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TUOZSP3 The European ERL Roadmap electron, gun, 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
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TUPOST016 Status of LLRF and Resonance Control Dedicated Algorithms Extension for PolFEL controls, cavity, resonance, operation 880
 
  • W. Jalmuzna, W. Cichalewski, A. Napieralski, P.S. Sekalski
    TUL-DMCS, Łódź, Poland
  
  PolFEL (POLish Free Electron Laser) is the new super-conducting based facility, which is under construction in Poland. It will provide a continuous electron beam with energy up to 160 MeV, which will be converted to light pulses with wavelengths as short as 150 nm. CW (Continuous Wave) operation of the superconducting linear accelerator with narrow bandwidth and high electromagnetic field gradient (presumably above 30 MV/m for single structure) creates new challenges while dealing with RF field stability, the influence of mechanical de-tuning of resonating structures and must take into account all limits induced by power amplifiers and cryo-system. The real-time control algorithm responsible for RF field, motor tuners, and piezo control must strictly interact with each other to provide the satisfactory performance of the whole facility. In addition, constant monitoring of such parameters as detuning, bandwidth, power margins of the amplifier, state of cavities must be done. The paper presents the current status of implementation of PolFEL’s LLRF Controller (extending GDR to other modes of operation as SEL, PLL) and Piezo Controller (both hardware and firmware layers).  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST016  
About • Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 03 July 2022
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TUPOST018 Long Pulse Operation of the E-XFEL Cryomodule cavity, operation, controls, LLRF 888
 
  • W. Cichalewski
    TUL-DMCS, Łódź, Poland
  • J.K. Sekutowicz
    DESY, Hamburg, Germany
  
  The CW operation becomes more attractive mode of beam and RF operation, even for infrastructures initially developed as pulsed experiments. Compared to the short (single ms) pulse the CW or long pulse (LP) operation allows for a more relaxed bunch scheme and enables higher bunch quantities during the experiment run. The Long Pulse operation scenario is one of the possible EXFEL modes of work in the future. LLRF systems that work in CW (and LP) are in operation worldwide. Most of them are dedicated to single cavity control. The XFEL dedicated system is capable of multicavity cryomodules vector-sum operation. In such a configuration switching from short-pulse operation into long-pulse with the existing limitations from the allowed cryo heat load level, average input power per coupler (and others) can be extremely challenging. For this setup the support from the dynamic resonance control system is essential. This paper summarizes efforts towards the successful vector-sum operation of the X-FEL type cryomodule in the LP operation mode. Modifications to the original LLRF setup together with challenges of narrow bandwidth operation in moderate and high gradients are discussed.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST018  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 21 June 2022 — Issue date ※ 23 June 2022
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TUPOST046 Machine Learning Applied for the Calibration of the Hard X-Ray Single-Shot Spectrometer at the European XFEL photon, controls, laser, operation 965
 
  • C. Grech, M.W. Guetg
    DESY, Hamburg, Germany
  • G. Geloni
    EuXFEL, Schenefeld, Germany
  
  Single-crystal monochromators are used in free electron lasers for hard x-ray self-seeding, selecting a very narrow spectral range of the original SASE signal for further amplification. When rotating the crystal around the roll and pitch axes, one can exploit several symmetric and asymmetric reflections as established by Bragg’s law. This work describes the implementation of a machine learning classifier to identify the crystal indices corresponding to a given reflection, and eventually calculate the difference between the photon energy as measured by a single-shot spectrometer and the actual one. The image processing techniques to extract the properties of the crystal reflection are described, as well as how this information is used to calibrate two spectrometer parameters.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOST046  
About • Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 24 June 2022 — Issue date ※ 09 July 2022
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TUPOPT005 Status of the Superconducting Soft X-Ray Free-Electron Laser User Facility FLASH laser, undulator, experiment, operation 1006
 
  • M. Vogt, C. Gerth, K. Honkavaara, M. Kuhlmann, J. Rönsch-Schulenburg, L. Schaper, S. Schreiber, R. Treusch, J. Zemella
    DESY, Hamburg, Germany
  
  The XUV and soft X-ray free-electron laser FLASH at DESY is capable of operating two undulator beamlines simultaneously with up to several thousand bunches per second. It is driven by a normal conducting RF photo-cathode gun and a superconducting L-band linac. FLASH is currently undergoing a substantial refurbishment and upgrade program (FLASH2020+). The first 9-months installation shutdown started in November 2021. Here we report on the operation in 2021 and present main upgrades during the ongoing shutdown.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT005  
About • Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 17 June 2022
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TUPOPT006 The New FLASH1 Beamline for the FLASH2020+ Project undulator, electron, 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  
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TUPOPT008 An Overview of the T20 Beamline for the LUXE Experiment at the European XFEL emittance, experiment, electron, 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 electron, 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
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TUPOPT011 Start To End Simulation Study For Oscillator-Amplifier Free-Electron Laser electron, radiation, simulation, 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 electron, 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
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TUPOPT014 The Status of the SASE3 Variable Polarization Project at the European XFEL undulator, polarization, vacuum, radiation 1029
 
  • S. Karabekyan, S. Abeghyan, M. Bagha-Shanjani, S. Casalbuoni, U. Englisch, W. Freund, G. Geloni, J. Grünert, S. Hauf, C. Holz, D. La Civita, J. Laksman, D. Mamchyk, M.P. Planas, F. Preisskorn, S. Serkez, H. Sinn, M. Wuenschel, M. Yakopov, C. Youngman
    EuXFEL, Schenefeld, Germany
  • P. Altmann, A. Block, W. Decking, L. Fröhlich, O. Hensler, T. Ladwig, D. Lenz, D. Lipka, R. Mattusch, N. Mildner, E. Negodin, J. Prenting, F. Saretzki, M. Schlösser, F. Schmidt-Föhre, E. Schneidmiller, M. Scholz, D. Thoden, T. Wamsat, T. Wilksen, T. Wohlenberg, M.V. Yurkov
    DESY, Hamburg, Germany
  • J. Bahrdt
    HZB, Berlin, Germany
  • M. Brügger, M. Calvi, S. Danner, R. Ganter, L. Huber, A. Keller, C. Kittel, X. Liang, S. Reiche, M.S. Schmidt, T. Schmidt, K. Zhang
    PSI, Villigen PSI, Switzerland
  • D.E. Kim
    PAL, Pohang, Republic of Korea
  • Y. Li
    IHEP, People’s Republic of China
  
  The undulator systems at the European XFEL consist of two hard X-ray systems, SASE1 and SASE2, and one soft X-ray system, SASE3. All three systems are equipped with planar undulators using permanent neodymium magnets. These systems allow the generation of linearly polarized radiation in the horizontal plane. In order to generate variable polarization radiation in the soft X-ray range, an afterburner is currently being implemented behind the SASE3 planar undulator system. It consists of four APPLE-X helical undulators. The project, called SASE 3 Variable Polarization, is close to being put into operation. All four helical undulators have been installed in the tunnel during the 2021-2022 winter shutdown. This paper describes the status of the project and the steps toward its commissioning. It also presents lessons learned during the implementation of the project.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT014  
About • Received ※ 02 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 05 July 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, electron, 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
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TUPOPT017 Start-to-end Simulations for Bunch Compressor and THz SASE FEL at PITZ simulation, booster, experiment, undulator 1037
 
  • A. Lueangaramwong, P. Boonpornprasert, M. Krasilnikov, X.-K. Li, F. Stephan
    DESY Zeuthen, Zeuthen, Germany
  
  The magnetic bunch compressor was designed as part of a THz accelerator source being developed at the Photo Injector Test facility at DESY in Zeuthen (PITZ) as a prototype for pump-probe experiments at the European XFEL. As an electron bunch is compressed to achieve higher bunch currents for the THz source, the beam dynamics in the bunch compressor was studied by numerical simulations. A start-to-end simulation optimizer including coherent synchrotron radiation (CSR) effects has been developed by combining the use of ASTRA, OCELOT, and GENESIS to support the design of the THz source prototype. In this paper we present simulation results to explore the possibility of improving the performance of the THz FEL at PITZ by using the developed bunch compressor.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT017  
About • Received ※ 18 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 13 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPOPT018 Fermi 2.0 Future Upgrade Strategy electron, 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
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TUPOPT019 FERMI FEL-1 Upgrade to EEHG laser, electron, 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
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TUPOPT023 Undulator Tapering Studies of an Echo-Enabled Harmonic Generation Based Free-Electron Laser undulator, electron, 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
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TUPOPT025 Concept of Electron Beam Diagnostics for PolFEL radiation, electron, 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 electron, radiation, 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)  
 
TUPOPT029 Infrared Free-Electron Laser Project in Thailand electron, 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 electron, 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 electron, 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
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TUPOPT035 Introduction of Westwood Linear Accelerator Test Facility in University of California Los Angeles gun, laser, electron, 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
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TUPOPT037 LCLS Multi-Bunch Improvement Plan: First Results kicker, linac, experiment, undulator 1092
 
  • A. Halavanau, A.L. Benwell, T.G. Beukers, L.B. Borzenets, F.-J. Decker, J. Hugyik, A. Ibrahimov, E.N. Jongewaard, A.K. Krasnykh, A.L. Le, K. Luchini, A.A. Lutman, A. Marinelli, M. Petree, A. Romero, A.V. Sy
    SLAC, Menlo Park, California, USA
  
  LCLS copper linac primarily operates in a single bunch mode with a repetition rate of 120 Hz. Presently, several in-house projects and LCLS user experiments require double- and multi-pulse trains of X-rays, with inter-pulse delay spanning between 0.35 and 220 ns. We discuss beam control improvements to the copper linac using ultra-fast stripline kicker, as well as additional photon diagnostics. We especially focus on a case of double-pulse mode, with 218 ns separation.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT037  
About • Received ※ 12 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 10 July 2022
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TUPOPT039 Characterization of Diamond with Buried Boron-Doped Layer Developed for Q-Switching an X-Ray Optical Cavity cavity, laser, lattice, ECR 1097
 
  • R.A. Margraf, A. Halavanau, Z. Huang, J. Krzywiński, J.P. MacArthur, G. Marcus, M.L. Ng, A.R. Robert, R. Robles, T. Sato, D. Zhu
    SLAC, Menlo Park, California, USA
  • Z. Huang, F. Ke, R. Robles, Y. Zhong
    Stanford University, Stanford, California, USA
  • S.-K. Mo, Y. Zhong
    LBNL, Berkeley, California, USA
  • P. Pradhan
    ANL, Lemont, Illinois, USA
  • A.R. Robert
    MAX IV Laboratory, Lund University, Lund, Sweden
  • M.D. Ynsa
    UAM, Madrid, Spain
  
  Funding: This work was supported by the Department of Energy, Laboratory Directed Research and Development program at SLAC National Accelerator Laboratory, under contract DE-AC02-76SF00515.
X-ray Free-Electron Laser Oscillators (XFELOs) and X-ray Regenerative Amplifier FELs (XRAFELs) are currently in development to improve longitudinal coherence and spectral brightness of XFELs. These schemes lase an electron beam in an undulator within an optical cavity to produce X-rays. X-rays circulate in the cavity and interact with fresh electron bunches to seed the FEL process over multiple passes, producing progressively brighter and more spectrally pure X-rays. Typically, the optical cavities used are composed of Bragg-reflecting mirrors to provide high reflectivity and spectral filtering. This high reflectivity necessitates special techniques to out-couple X-rays from the cavity to deliver them to users. One method involves "Q-switching" the cavity by actively modifying the reflectivity of one Bragg-reflecting crystal. To control the crystal lattice constant and thus reflectivity, we use an infrared laser to heat a buried boron layer in a diamond crystal. Here, we build on earlier work in Krzywinski et al.* and present the current status of our Q-switching diamond, including implantation with 9 MeV boron ions, annealing, characterization and early tests.
*Krzywinski et al., "Q-switching of X-Ray Optical Cavities by using Boron Doped Buried Layer under a Surface of a Diamond Crystal," Proceedings of FEL2019, Hamburg, Germany, TUP033, 2019. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT039  
About • Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 08 July 2022
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TUPOPT047 Progress Report on Population Inversion X-Ray Laser Oscillator at LCLS cavity, laser, target, experiment 1107
 
  • A. Halavanau, R. Alonso-Mori, A. Aquila, U. Bergmann, F.-J. Decker, F. Fuller, M. Liang, A.A. Lutman, R.A. Margraf, R.H. Paul, C. Pellegrini
    SLAC, Menlo Park, California, USA
  • R. Ash, N.B. Welke
    UW-Madison/PD, Madison, Wisconsin, USA
  • A.I. Benediktovitch
    DESY, Hamburg, Germany
  • S.C. Krusic
    JSI, Ljubljana, Slovenia
  • N. Majernik, P. Manwani, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • R. Robles
    Stanford University, Stanford, California, USA
  • N. Rohringer
    Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
  
  We report the progress in the design and construction of a population inversion x-ray laser oscillator (XLO) using LCLS as an x-ray laser pump, being developed by a SLAC, CFEL, University of Hamburg (Germany), University of Wisconsin, Josef Stefan Institute (Slovenia) and UCLA collaboration. In this proceeding, we will present the latest XLO design and numerical simulations substantiated by our first experimental results. In our next experimental step XLO will be tested on the Coherent X-ray Imaging (CXI) end-station at LCLS as a two pass Regenerative Amplifier operating at the Copper Kα1 photon energy of 8048 eV. When built, XLO will generate fully coherent transform limited pulses with about 50 meV FWHM bandwidth. We expect the XLO will pave the way for new user experiments, e.g. in inelastic x-ray scattering, parametric down conversion, quantum science, x-ray interferometry, and external hard x-ray XFEL seeding.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT047  
About • Received ※ 12 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 24 June 2022
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TUPOPT051 Reconstruction and Beam-Transport Study of the cERL Dump Line for High-Power IR-FEL Operation cavity, operation, beam-transport, electron 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
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TUPOPT062 A Data-Driven Anomaly Detection on SRF Cavities at the European XFEL cavity, network, SRF, experiment 1152
 
  • A. Sulc, A. Eichler, T. Wilksen
    DESY, Hamburg, Germany
  
  Funding: This work was supported by HamburgX grant LFF-HHX-03 to the Center for Data and Computing in Natural Sciences (CDCS) from the Hamburg Ministry of Science, Research, Equalities and Districts.
The European XFEL is currently operating with hundreds of superconducting radio frequency cavities. To be able to minimize the downtimes, prevention of failures on the SRF cavities is crucial. In this paper, we propose an anomaly detection approach based on a neural network model to predict occurrences of breakdowns on the SRF cavities based on a model trained on historical data. We used our existing anomaly detection infrastructure to get a subset of the stored data labeled as faulty. We experimented with different training losses to maximally profit from the available data and trained a recurrent neural network that can predict a failure from a series of pulses. The proposed model is using a tailored architecture with recurrent neural units and takes into account the sequential nature of the problem which can generalize and predict a variety of failures that we have been experiencing in operation. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT062  
About • Received ※ 17 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 24 June 2022
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TUPOPT065 Dispersion-Free Steering Beam Based Alignment at SwissFEL undulator, quadrupole, electron, 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  
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TUPOMS013 Novel High Repetition Rate CW SRF Linac-Based Multispectral Photon Source electron, 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
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TUPOMS024 Sensitivity of EEHG Simulations to Dynamic Beam Parameters electron, 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
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TUPOMS053 Start-to-End Simulations of the LCLS-II HE Free Electron Laser electron, 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
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WEPOST034 Magnetic Characterization of a Superconducting Transverse Gradient Undulator for Compact Laser Wakefield Accelerator-Driven FELs undulator, laser, electron, 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
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WEPOMS024 Present Status of the Injector at the Compact ERL at KEK gun, emittance, linac, operation 2296
 
  • O.A. Tanaka, T. Miyajima, T. Tanikawa
    KEK, Ibaraki, Japan
  
  The Compact ERL at KEK is a test accelerator to develop ERL technologies and their possible applications. The first target of injector operation to demonstrate IR-FEL was to generate high bunch charge electron beams with low longitudinal emittance and short bunch length. In 2020, the injector was operated with the bunch charge of 60 pC, the DC gun voltage of 480 kV, the injector energy of 5 MeV and the bunch length of 2 ps rms, and the required beam quality for the IR-FEL has been achieved for a single-pass operation mode. The next target is to demonstrate IR-FEL generation for recirculation mode. The injector energy is decreased to 3.5 MeV due to a limitation of the energy ratio between injection and recirculation beams. Moreover, the DC gun voltage decreases to 390 kV due to the troubles of the DC gun. Therefore, control of the space charge effect is more important to design and optimize the beam transport condition of the injector. In this report, a strategy of the injector optimization together with its realization results and future prospects are summarized.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS024  
About • Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 19 June 2022 — Issue date ※ 21 June 2022
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WEPOMS025 Injector Design Towards ERL-Based EUV-FEL for Lithography emittance, cavity, electron, 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
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WEPOMS037 Microbunching Studies for the FLASH2020+ Upgrade Using a Semi-Lagrangian Vlasov Solver bunching, simulation, laser, electron 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
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WEPOMS039 Analysis of Xcos Simulation Model for Intensity at Third and Fifth Harmonics Undulator Radiation undulator, radiation, electron, simulation 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
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THOXSP3 Path to High Repetition Rate Seeding: Combining High Gain Harmonic Generation with an Optical Klystron electron, 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
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THIYGD1 White Rabbit Based Beam-Synchronous Timing Systems for SHINE timing, network, electron, 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
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THPOST009 Simulation Study of a Bunch Compressor for an Accelerator-Based THz Source at the European XFEL electron, 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
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THPOST029 Upgrade of the Slow Extraction System of the Heidelberg Ion-Beam Therapy Centre’s Synchrotron extraction, synchrotron, experiment, feedback 2509
 
  • E. Feldmeier, R. Cee, E.C. Cortés García, M. Galonska, Th. Haberer, M. Hun, A. Peters, S. Scheloske, C. Schömers
    HIT, Heidelberg, Germany
  
  The Heidelberg Ion-Beam Therapy Centre HIT consists of a linear accelerator and a synchrotron to provide carbon ions, helium ions and protons for the clinical use as well as oxygen ions for experiments. The RF-KO slow extraction method is used to extract the particles from the synchrotron. To improve the spill quality of the extracted beam a new RF-signal was investigated which increases the R-value from 92.5% to 97,5%. The signal is a multiband RF signal broadened with a random BPSK at 3 frequency bands.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST029  
About • Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 24 June 2022
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THPOPT015 The Design of the Full Energy Beam Exploitation (FEBE) Beamline on CLARA experiment, laser, electron, diagnostics 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
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THPOPT027 R&D on High QE Photocathodes at INFN LASA cathode, gun, operation, electron 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
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THPOPT031 SUNDAE1: A Liquid Helium Vertical Test-Stand for 2m Long Superconducting Undulator Coils undulator, photon, power-supply, experiment 2646
 
  • B. Marchetti, S. Abeghyan, J.E. Baader, S. Casalbuoni, M. Di Felice, U. Englisch, V. Grattoni, D. La Civita, M. Vannoni, M. Yakopov, P. Ziolkowski
    EuXFEL, Schenefeld, Germany
  • S. Barbanotti, H.-J. Eckoldt, A. Hauberg, K. Jensch, S. Lederer, L. Lilje, R. Ramalingam, T. Schnautz, R. Zimmermann
    DESY, Hamburg, Germany
  • A.W. Grau
    KIT, Karlsruhe, Germany
  
  Superconducting Undulators (SCUs) can produce higher photon flux and cover a wider photon energy range compared to permanent magnet undulators (PMUs) with the same vacuum gap and period length. To build the know-how to implement superconducting undulators for future upgrades of the European XFEL facility, two magnetic measurement test stands named SUNDAE 1 and 2 (Superconducting UNDulAtor Experiment) are being developed. SUNDAE1 will facilitate research and development on magnet design thanks to the possibility of training new SCU coils and characterizing their magnetic field. The experimental setup will allow the characterization of magnets up to 2m in length. These magnets will be immersed in a Helium bath at 2K or 4K temperature. In this article, we describe the experimental setup and highlight its expected performances.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT031  
About • Received ※ 03 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 17 June 2022
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THPOPT032 SUNDAE2 at EuXFEL: A Test Stand to Characterize the Magnetic Field of Superconducting Undulators undulator, vacuum, laser, experiment 2649
 
  • J.E. Baader, S. Abeghyan, S. Casalbuoni, D. La Civita, B. Marchetti, M. Yakopov, P. Ziolkowski
    EuXFEL, Schenefeld, Germany
  • H.-J. Eckoldt, A. Hauberg, S. Lederer, L. Lilje, T. Wohlenberg, R. Zimmermann
    DESY, Hamburg, Germany
  • A.W. Grau
    KIT, Eggenstein-Leopoldshafen, Germany
  
  European XFEL foresees a superconducting undulator (SCU) afterburner in the SASE2 hard X-ray beamline. It consists of six 5m-long undulator modules with a 5mm vacuum gap, where each module contains two 2m-long coils and one phase shifter. Prior to installation, the magnetic field must be mapped appropriately. Two magnetic measurement test stands named SUNDAE 1 and 2 (Superconducting UNDulAtor Experiment) are being developed at European XFEL. While SUNDAE1 will be a vertical test stand to measure SCU coils up to two meters with Hall probes in a liquid or superfluid helium bath, SUNDAE2 will measure the SCU coils assembled in the final cryostat. This contribution presents the development status of SUNDAE2 and its main requirements.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT032  
About • Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022
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THPOPT044 The Alkali-Metal Photocathode Preparation Facility at Daresbury Laboratory: First Caesium Telluride Deposition Results cathode, electron, MMI, emittance 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
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THPOPT058 Status and Powering Test Results of HTS Undulator Coils at 77 K for Compact FEL Designs undulator, wiggler, photon, superconductivity 2726
 
  • S.C. Richter, A. Bernhard, A.-S. Müller
    KIT, Karlsruhe, Germany
  • A. Ballarino, T.H. Nes, S.C. Richter, D. Schoerling
    CERN, Meyrin, Switzerland
  
  Funding: This work has been supported by the Wolfgang Gentner Program of the German Federal Ministry of Education and Research (grant no. 05E18CHA).
The production of low emittance positron beams for future linear and circular lepton colliders, like CLIC or FCC-ee, requires high-field damping wigglers. Just as compact free-electron lasers (FELs) require high-field but as well short-period undulators to emit high energetic, coherent photons. Using high-temperature superconductors (HTS) in the form of coated ReBCO tape superconductors allows higher magnetic field amplitudes at 4 K and larger operating margins as compared to low-temperature superconductors, like Nb-Ti. This contribution discusses the development work on superconducting vertical racetrack (VR) undulator coils, wound from coated ReBCO tape superconductors. The presented VR coils were modularly designed with a period length of 13 mm. Powering tests in liquid nitrogen of multiple vertical racetrack coils were performed at CERN. The results from the measurements are presented for three VR coils and compared with electromagnetic simulations. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT058  
About • Received ※ 17 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 21 June 2022
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THPOPT060 Tolerance Study on the Geometrical Errors for a Planar Superconducting Undulator undulator, simulation, MMI, FEM 2734
 
  • V. Grattoni, S. Casalbuoni, B. Marchetti
    EuXFEL, Schenefeld, Germany
  
  At the European XFEL, a superconducting afterburner is considered for the SASE2 hard X-ray beamline. It will consist of six undulator modules. Within each module, two superconducting undulators (SCU) 2 m long are present. Such an afterburner will enable photon energies above 30 keV. A high field quality of the SCU is crucial to guarantee the quality of the electron beam trajectory, which is directly related to the spectral quality of the emitted free-electron laser (FEL) radiation. Therefore, the effects of the SCU’s mechanical imperfections on the resultant magnetic field have to be carefully characterized. In this contribution, we present possible mechanical errors affecting the undulator structure, and we perform an analytical study aimed at determining the tolerances on these errors for our SCUs.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT060  
About • Received ※ 03 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 27 June 2022
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THPOPT061 European XFEL Undulators - Status and Plans undulator, photon, electron, 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
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THPOTK010 Development of a Short Period Superconducting Helical Undulator undulator, electron, 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  
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THPOTK041 Development of Programmable Bipolar Multi kHz Kicker Drivers for Long Pulse Superconducting Electron Linacs kicker, electron, 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
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THPOTK053 Foiled Again: Solid-State Sample Delivery for High Repetition Rate XFELs laser, target, experiment, controls 2899
 
  • N. Majernik, N. Inzunza, P. Manwani, J.B. Rosenzweig
    UCLA, Los Angeles, California, USA
  • R.B. Agustsson, A. Moro
    RadiaBeam, Santa Monica, California, USA
  • R. Ash, N.B. Welke
    UW-Madison/PD, Madison, Wisconsin, USA
  • U. Bergmann, A. Halavanau, C. Pellegrini
    SLAC, Menlo Park, California, USA
  
  Funding: Department of Energy DE-SC0009914 and DE-AC02-76SF00515
XFELs today are capable of delivering high intensity pulse trains of x-rays with up-to MHz to sub-GHz frequency. These x-rays, when focused, can ablate a sample in a single shot, requiring the sample material to be replaced in time for the next shot. For some applications, especially serial crystallography, the sample may be renewed as a dilute solution in a high speed jet. Here, we describe the development and characterization of a system to deliver solid state sample material to an XFEL nanofocus. The first application of this system will be an x-ray laser oscillator operating at the copper Kα line with a ~30 ns cavity. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK053  
About • Received ※ 06 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 02 July 2022
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THPOMS032 Advances in the Optimization of Medical Accelerators proton, network, medical-accelerators, detector 3030
 
  • 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 675265.
Between 2016 and 2020, 15 Fellows have carried out collaborative research within the 4 M€ Optimization of Medical Accelerators (OMA) EU-funded innovative train-ing network. Based at universities, research and clinical facilities, as well as industry partners in several European countries, the Fellows have successfully developed a range of beam and patient imaging techniques, improved biological and physical models in Monte Carlo codes, and also helped improve the design of existing and future clinical facilities. This contribution presents three selected OMA research highlights: the use of Medipix3 for dosimetry and real-time beam monitoring, studies into the technical challenges for FLASH proton therapy, recognized by the European Journal of Medical Physics’ 2021 Galileo Gali-lei Award, and research into novel monitors for in-vivo dosimetry that emerged on the back of the OMA network. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS032  
About • Received ※ 05 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 02 July 2022
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THPOMS056 An Overview of the Applications of MIR and THz Spectroscopy in Astrochemistry Studies experiment, detector, electron, 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
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