IPAC2022 - List of Keywords (synchrotron-radiation)

Paper	Title	Other Keywords	Page
MOPOPT024	Measuring the Coherent Synchrotron Radiation Far Field with Electro-Optical Techniques	laser, detector, radiation, synchrotron	292
	C. Widmann, M. Brosi, E. Bründermann, S. Funkner, A.-S. Müller, M.J. Nasse, G. Niehues, M.-D. Noll, M.M. Patil, M. Reißig, J.L. Steinmann KIT, Karlsruhe, Germany M. Brosi MAX IV Laboratory, Lund University, Lund, Sweden
	Funding: M. M. P. acknowledges the support by the DFG-funded Doctoral School KSETA. C. W. achnowledges funding by BMBF contract number 05K19VKD. For measuring the temporal profile of the coherent synchrotron radiation (CSR) a setup based on electro-optical spectral decoding (EOSD) will be installed as part of the sensor network at the KIT storage ring KARA (Karlsruhe Research Accelerator). The EOSD technique allows a single-shot, phase sensitive measurement of the complete spectrum of the CSR far field radiation at each turn. Therefore, the dynamics of the bunch evolution, e.g. the microbunching, can be observed in detail. Especially, in synchronized combination with the already established near-field EOSD, this method could provide deeper insights in the interplay of bunch profile and CSR generation for each individual electron bunch. For a successful implementation of the EOSD single shot setup, measurements with electro-optical sampling (EOS) are performed. With EOS the THz pulse shape is scanned over several turns by shifting the delay of laser and THz pulse. In this contribution different steps towards the installation of the EOSD far field setup are summarized.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT024
About •	Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 08 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOXGD1	Design and Construction of Optical System of the Coronagraph for Beam Halo Observation in the SuperKEKB	radiation, scattering, synchrotron, electron	769
	G. Mitsuka, H. Ikeda, T.M. Mitsuhashi KEK, Ibaraki, Japan
	For the observation of beam halo, the coronagraph is designed and constructed in the SuperKEKB. The coronagraph has three stages of optical systems, objective system, re-diffraction system and relay system. Since the SR monitor of SuperKEKB has a long optical path (60 m), we need an objective system with long focal length. The Aperture limit is determined by the diamond mirror which is set in 23.6 m from the source point. Therefore, we must assign this aperture for the entrance pupil of the objective system. For satisfying these conditions, we design a reflective telephoto system based on the Gregorian telescope for the objective system. The focal length is designed to 7028 mm. and front principal point position is designed to the position of diamond mirror. The result of construction, the performance of the objective system has a diffraction limited quality. The re-diffraction system and relay system are also designed based on Kepler type telescope. The result of optical testing using the beam in the HER, we achieved a contrast of 6 order magnitude. Some early result for the observation of beam halo in the HER will also present in this presentation.
	Slides TUOXGD1 [4.345 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOXGD1
About •	Received ※ 09 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS021	PETRA III Operational Performance and Availability	operation, synchrotron, experiment, dipole	1453
	R. Wanzenberg, M. Bieler, J. Keil, L. Liao, G.K. Sahoo, M. Schaumann DESY, Hamburg, Germany
	At DESY the Synchrotron Light Source PETRA III offers scientists outstanding opportunities for experiments with hard X-rays of exceptionally high brilliance since 2009. The light source is operated mainly in two operation modes with 480 and 40 bunches at a beam energy of 6 GeV. With the completion of the last milestone of the extension project in summer 2021 that brought the new dipole beamline P66 into operation, 2022 is the first year where almost 5000 hours of user run time could be scheduled. This paper will review the statistics of availability and failures over the years and provides a detailed description of the operation in 2021. Additionally, an outlook for the next runs is given.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS021
About •	Received ※ 19 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOXGD2	Electron Accelerator Lattice Design for LHeC with Permanent Magnets	electron, linac, synchrotron, radiation	1587
	D. Trbojevic, J.S. Berg, S.J. Brooks BNL, Upton, New York, USA S.A. Bogacz JLab, Newport News, Virginia, USA G.H. Hoffstaetter Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work performed under the Contract Number DE-AC02-98CH10886 with the auspices of US Department of Energy We present a new ’green energy’ approach to the Energy Recovery Linac (ERL) the future Electron Ion Collider at LHeC using single beam line made of very strong focusing combined function permanent magnets and the Fixed Field Alternating Linear Gradient (FFA-LG) principle. We are basing our design on recent very successful commissioning results of the Cornell University and Brookhaven National Laboratory ERL Test Accelerator-CBETA.
	Slides WEOXGD2 [19.845 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOXGD2
About •	Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 02 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK057	Towards Direct Detection of the Shape of CSR Pulses with Fast THz Detectors	detector, radiation, synchrotron, electron	2190
	J.L. Steinmann, M. Brosi, E. Bründermann, A. Mochihashi, A.-S. Müller, P. Schreiber KIT, Karlsruhe, Germany
	Funding: We acknowledge in part support by the Helmholtz President’s strategic fund IVF "Plasma accelerators". This work is funded in part by the BMBF contract number: 05K19VKD. Coherent synchrotron radiation (CSR) is emitted when the emitting structure is equal to or smaller than the observed wavelength. Consequently, these pulses are very short and most detectors respond with their impulse response, regardless of the pulse length and shape. Here we present single-shot measurements performed at the Karlsruhe Research Accelerator (KARA) using a fast real-time oscilloscope and Schottky barrier detectors sensitive in the sub-THz range. The time response of this setup to CSR pulses emitted by electron bunches during the microbunching instability is shown to be sensitive to the shape of the electron bunch. Our results show how, in the future, the shape of electron bunches can be directly measured using a straightforward setup.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK057
About •	Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 09 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOMS013	Neural Network Solver for Coherent Synchrotron Radiation Wakefield Calculations in Accelerator-Based Charged Particle Beams	simulation, radiation, wakefield, synchrotron	2261
	A.L. Edelen, C. Emma, C.E. Mayes, R.J. Roussel SLAC, Menlo Park, California, USA
	Particle accelerators support a wide array of scientific, industrial, and medical applications. To meet the needs of these applications, accelerator physicists rely heavily on detailed simulations of the complicated particle beam dynamics through the accelerator. One of the most computationally expensive and difficult-to-model effects is the impact of Coherent Synchrotron Radiation (CSR). CSR is one of the major drivers of growth in the beam emittance, which is a key metric of beam quality that is critical in many applications. The CSR wakefield is very computationally intensive to compute with traditional electromagnetic solvers, and this is a major limitation in accurately simulating accelerators. Here, we demonstrate a new approach for the CSR wakefield computation using a neural network solver structured in a way that is readily generalizable to new setups. We validate its performance by adding it to a standard beam tracking test problem and show a ten-fold speedup along with high accuracy.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS013
About •	Received ※ 10 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT028	Dependence of CsK2Sb Photocathode Performance on the Quality of Graphene Substrate Film	cathode, laser, electron, synchrotron	2637
	L. Guo, K. Goto, Y. Takashima Nagoya University, Nagoya, Japan H. Yamaguchi LANL, Los Alamos, New Mexico, USA M. Yamamoto KEK, Ibaraki, Japan
	Funding: U.S.-Japan Science and Technology Cooperation Program in High Energy Physics A photocathode that extracts electrons by irradiating a semiconductor or metal with a laser is applied to advanced accelerators and electron microscopes as a high-performance cathode. In particular, the CsK2Sb photocathode is of interest because it has features such as low emittance, excitability with visible light, and high quantum efficiency. Generally, the CsK2Sb photocathode is produced by depositing a cathode element on a substrate, so that the cathode performance strongly depends on the surface condition of the substrate. We have found graphene as reusable substrate, which has the property of being chemically inactive. In this study, graphene film quality dependence of CsK2Sb photo-cathode performance was evaluated. Specifically, CsK2Sb cathode was deposited using different quality graphene film substrates and their QE values and uniformity were compared. The quality of graphene films was analyzed using X-ray Photoelectron Spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). We found that the graphene film can be cleaned by heating at 500 deg. The QE of the cathode on a good quality graphene film was higher and more uniform than that on a poor quality graphene film.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT028
About •	Received ※ 16 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 10 June 2022 — Issue date ※ 24 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT067	Propagation of Gaussian Wigner Function Through a Matrix-Aperture Beamline	radiation, synchrotron, emittance, ECR	2755
	B. Nash, D.T. Abell, P. Moeller, I.V. Pogorelov RadiaSoft LLC, Boulder, Colorado, USA N.B. Goldring STATE33 Inc., Portland, Oregon, USA
	Funding: This work is supported by the US Department of Energy, Office of Basic Energy Sciences under Award No. DE-SC0020593. We develop a simplified beam propagation model for x-ray beamlines that includes partial coherence as well as the impact of apertures on the beam. In particular, we consider a general asymmetric Gaussian Schell model, which also corresponds to a Gaussian Wigner function. The radiation is thus represented by a 4x4 symmetric second moment matrix. We approximate rectangular apertures by Gaussian apertures, taking care that the loss in flux is the same for the two models. The beam will thus stay Gaussian through both linear transport and passage through the apertures, allowing a self-consistent picture. We derive expressions for decrease in flux and changes in second moments upon passage through the aperture. We also derive expressions for the coherence lengths and analyze how these propagate through linear transport and Gaussian apertures. We apply our formalism to cases of low emittance light source beamlines and develop a better understanding about trade-offs between coherence length increase and flux reduction while passing through physical apertures. Our formulae are implemented in RadiaSoft’s Sirepo Shadow application allowing easy use for realistic beamline models.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT067
About •	Received ※ 09 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT068	Linear Canonical Transform Library for Fast Coherent X-Ray Wavefront Propagation	optics, radiation, synchrotron, operation	2759
	B. Nash, D.T. Abell, P. Moeller, I.V. Pogorelov RadiaSoft LLC, Boulder, Colorado, USA N.B. Goldring STATE33 Inc., Portland, Oregon, USA
	Funding: This work is supported by the US Department of Energy, Office of Basic Energy Sciences under Award No. DE-SC0020593. X-ray beamlines are essential components of all synchrotron light sources, transporting radiation from the stored electron beam passing from the source to the sample. The linear optics of the beamline can be captured via an ABCD matrix computed using a ray tracing code. Once the transport matrix is available, one may then include diffraction effects and arbitrary wavefront structure by using that same information in a Linear Canonical Transform (LCT) applied to the initial wavefront. We describe our implementation of a Python-based LCT library for 2D synchrotron radiation wavefronts. We have thus far implemented the separable case and are in the process of implementing algorithms for the non-separable case. Rectangular apertures are also included. We have tested our work against corresponding wavefront computations using The Synchrotron Radiation Workshop (SRW) code. LCT vs. SRW timing and benchmark comparisons are given for undulator and bending magnet beamlines. This algorithm is being included in the Sirepo implementation of the Shadow ray tracing code. Finally, we describe our plans for application to partially coherent radiation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT068
About •	Received ※ 15 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)

Paper

Title

Other Keywords

Page

MOPOPT024

Measuring the Coherent Synchrotron Radiation Far Field with Electro-Optical Techniques

laser, detector, radiation, synchrotron

292

C. Widmann, M. Brosi, E. Bründermann, S. Funkner, A.-S. Müller, M.J. Nasse, G. Niehues, M.-D. Noll, M.M. Patil, M. Reißig, J.L. Steinmann
KIT, Karlsruhe, Germany
M. Brosi
MAX IV Laboratory, Lund University, Lund, Sweden

Funding: M. M. P. acknowledges the support by the DFG-funded Doctoral School KSETA. C. W. achnowledges funding by BMBF contract number 05K19VKD.
For measuring the temporal profile of the coherent synchrotron radiation (CSR) a setup based on electro-optical spectral decoding (EOSD) will be installed as part of the sensor network at the KIT storage ring KARA (Karlsruhe Research Accelerator). The EOSD technique allows a single-shot, phase sensitive measurement of the complete spectrum of the CSR far field radiation at each turn. Therefore, the dynamics of the bunch evolution, e.g. the microbunching, can be observed in detail. Especially, in synchronized combination with the already established near-field EOSD, this method could provide deeper insights in the interplay of bunch profile and CSR generation for each individual electron bunch. For a successful implementation of the EOSD single shot setup, measurements with electro-optical sampling (EOS) are performed. With EOS the THz pulse shape is scanned over several turns by shifting the delay of laser and THz pulse. In this contribution different steps towards the installation of the EOSD far field setup are summarized.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT024

About •

Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 08 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUOXGD1

Design and Construction of Optical System of the Coronagraph for Beam Halo Observation in the SuperKEKB

radiation, scattering, synchrotron, electron

769

G. Mitsuka, H. Ikeda, T.M. Mitsuhashi
KEK, Ibaraki, Japan

For the observation of beam halo, the coronagraph is designed and constructed in the SuperKEKB. The coronagraph has three stages of optical systems, objective system, re-diffraction system and relay system. Since the SR monitor of SuperKEKB has a long optical path (60 m), we need an objective system with long focal length. The Aperture limit is determined by the diamond mirror which is set in 23.6 m from the source point. Therefore, we must assign this aperture for the entrance pupil of the objective system. For satisfying these conditions, we design a reflective telephoto system based on the Gregorian telescope for the objective system. The focal length is designed to 7028 mm. and front principal point position is designed to the position of diamond mirror. The result of construction, the performance of the objective system has a diffraction limited quality. The re-diffraction system and relay system are also designed based on Kepler type telescope. The result of optical testing using the beam in the HER, we achieved a contrast of 6 order magnitude. Some early result for the observation of beam halo in the HER will also present in this presentation.

Slides TUOXGD1 [4.345 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOXGD1

About •

Received ※ 09 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS021

PETRA III Operational Performance and Availability

operation, synchrotron, experiment, dipole

1453

R. Wanzenberg, M. Bieler, J. Keil, L. Liao, G.K. Sahoo, M. Schaumann
DESY, Hamburg, Germany

At DESY the Synchrotron Light Source PETRA III offers scientists outstanding opportunities for experiments with hard X-rays of exceptionally high brilliance since 2009. The light source is operated mainly in two operation modes with 480 and 40 bunches at a beam energy of 6 GeV. With the completion of the last milestone of the extension project in summer 2021 that brought the new dipole beamline P66 into operation, 2022 is the first year where almost 5000 hours of user run time could be scheduled. This paper will review the statistics of availability and failures over the years and provides a detailed description of the operation in 2021. Additionally, an outlook for the next runs is given.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS021

About •

Received ※ 19 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEOXGD2

Electron Accelerator Lattice Design for LHeC with Permanent Magnets

electron, linac, synchrotron, radiation

1587

D. Trbojevic, J.S. Berg, S.J. Brooks
BNL, Upton, New York, USA
S.A. Bogacz
JLab, Newport News, Virginia, USA
G.H. Hoffstaetter
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work performed under the Contract Number DE-AC02-98CH10886 with the auspices of US Department of Energy
We present a new ’green energy’ approach to the Energy Recovery Linac (ERL) the future Electron Ion Collider at LHeC using single beam line made of very strong focusing combined function permanent magnets and the Fixed Field Alternating Linear Gradient (FFA-LG) principle. We are basing our design on recent very successful commissioning results of the Cornell University and Brookhaven National Laboratory ERL Test Accelerator-CBETA.

Slides WEOXGD2 [19.845 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEOXGD2

About •

Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 02 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK057

Towards Direct Detection of the Shape of CSR Pulses with Fast THz Detectors

detector, radiation, synchrotron, electron

2190

J.L. Steinmann, M. Brosi, E. Bründermann, A. Mochihashi, A.-S. Müller, P. Schreiber
KIT, Karlsruhe, Germany

Funding: We acknowledge in part support by the Helmholtz President’s strategic fund IVF "Plasma accelerators". This work is funded in part by the BMBF contract number: 05K19VKD.
Coherent synchrotron radiation (CSR) is emitted when the emitting structure is equal to or smaller than the observed wavelength. Consequently, these pulses are very short and most detectors respond with their impulse response, regardless of the pulse length and shape. Here we present single-shot measurements performed at the Karlsruhe Research Accelerator (KARA) using a fast real-time oscilloscope and Schottky barrier detectors sensitive in the sub-THz range. The time response of this setup to CSR pulses emitted by electron bunches during the microbunching instability is shown to be sensitive to the shape of the electron bunch. Our results show how, in the future, the shape of electron bunches can be directly measured using a straightforward setup.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK057

About •

Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 09 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOMS013

Neural Network Solver for Coherent Synchrotron Radiation Wakefield Calculations in Accelerator-Based Charged Particle Beams

simulation, radiation, wakefield, synchrotron

2261

A.L. Edelen, C. Emma, C.E. Mayes, R.J. Roussel
SLAC, Menlo Park, California, USA

Particle accelerators support a wide array of scientific, industrial, and medical applications. To meet the needs of these applications, accelerator physicists rely heavily on detailed simulations of the complicated particle beam dynamics through the accelerator. One of the most computationally expensive and difficult-to-model effects is the impact of Coherent Synchrotron Radiation (CSR). CSR is one of the major drivers of growth in the beam emittance, which is a key metric of beam quality that is critical in many applications. The CSR wakefield is very computationally intensive to compute with traditional electromagnetic solvers, and this is a major limitation in accurately simulating accelerators. Here, we demonstrate a new approach for the CSR wakefield computation using a neural network solver structured in a way that is readily generalizable to new setups. We validate its performance by adding it to a standard beam tracking test problem and show a ten-fold speedup along with high accuracy.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS013

About •

Received ※ 10 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT028

Dependence of CsK2Sb Photocathode Performance on the Quality of Graphene Substrate Film

cathode, laser, electron, synchrotron

2637

L. Guo, K. Goto, Y. Takashima
Nagoya University, Nagoya, Japan
H. Yamaguchi
LANL, Los Alamos, New Mexico, USA
M. Yamamoto
KEK, Ibaraki, Japan

Funding: U.S.-Japan Science and Technology Cooperation Program in High Energy Physics
A photocathode that extracts electrons by irradiating a semiconductor or metal with a laser is applied to advanced accelerators and electron microscopes as a high-performance cathode. In particular, the CsK2Sb photocathode is of interest because it has features such as low emittance, excitability with visible light, and high quantum efficiency. Generally, the CsK2Sb photocathode is produced by depositing a cathode element on a substrate, so that the cathode performance strongly depends on the surface condition of the substrate. We have found graphene as reusable substrate, which has the property of being chemically inactive. In this study, graphene film quality dependence of CsK2Sb photo-cathode performance was evaluated. Specifically, CsK2Sb cathode was deposited using different quality graphene film substrates and their QE values and uniformity were compared. The quality of graphene films was analyzed using X-ray Photoelectron Spectroscopy (XPS) and X-ray absorption spectroscopy (XAS). We found that the graphene film can be cleaned by heating at 500 deg. The QE of the cathode on a good quality graphene film was higher and more uniform than that on a poor quality graphene film.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT028

About •

Received ※ 16 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 10 June 2022 — Issue date ※ 24 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT067

Propagation of Gaussian Wigner Function Through a Matrix-Aperture Beamline

radiation, synchrotron, emittance, ECR

2755

B. Nash, D.T. Abell, P. Moeller, I.V. Pogorelov
RadiaSoft LLC, Boulder, Colorado, USA
N.B. Goldring
STATE33 Inc., Portland, Oregon, USA

Funding: This work is supported by the US Department of Energy, Office of Basic Energy Sciences under Award No. DE-SC0020593.
We develop a simplified beam propagation model for x-ray beamlines that includes partial coherence as well as the impact of apertures on the beam. In particular, we consider a general asymmetric Gaussian Schell model, which also corresponds to a Gaussian Wigner function. The radiation is thus represented by a 4x4 symmetric second moment matrix. We approximate rectangular apertures by Gaussian apertures, taking care that the loss in flux is the same for the two models. The beam will thus stay Gaussian through both linear transport and passage through the apertures, allowing a self-consistent picture. We derive expressions for decrease in flux and changes in second moments upon passage through the aperture. We also derive expressions for the coherence lengths and analyze how these propagate through linear transport and Gaussian apertures. We apply our formalism to cases of low emittance light source beamlines and develop a better understanding about trade-offs between coherence length increase and flux reduction while passing through physical apertures. Our formulae are implemented in RadiaSoft’s Sirepo Shadow application allowing easy use for realistic beamline models.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT067

About •

Received ※ 09 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 17 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT068

Linear Canonical Transform Library for Fast Coherent X-Ray Wavefront Propagation

optics, radiation, synchrotron, operation

2759

B. Nash, D.T. Abell, P. Moeller, I.V. Pogorelov
RadiaSoft LLC, Boulder, Colorado, USA
N.B. Goldring
STATE33 Inc., Portland, Oregon, USA

Funding: This work is supported by the US Department of Energy, Office of Basic Energy Sciences under Award No. DE-SC0020593.
X-ray beamlines are essential components of all synchrotron light sources, transporting radiation from the stored electron beam passing from the source to the sample. The linear optics of the beamline can be captured via an ABCD matrix computed using a ray tracing code. Once the transport matrix is available, one may then include diffraction effects and arbitrary wavefront structure by using that same information in a Linear Canonical Transform (LCT) applied to the initial wavefront. We describe our implementation of a Python-based LCT library for 2D synchrotron radiation wavefronts. We have thus far implemented the separable case and are in the process of implementing algorithms for the non-separable case. Rectangular apertures are also included. We have tested our work against corresponding wavefront computations using The Synchrotron Radiation Workshop (SRW) code. LCT vs. SRW timing and benchmark comparisons are given for undulator and bending magnet beamlines. This algorithm is being included in the Sirepo implementation of the Shadow ray tracing code. Finally, we describe our plans for application to partially coherent radiation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT068

About •

Received ※ 15 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)