ICAP2018 - List of Keywords (radiation)

Paper	Title	Other Keywords	Page
SAPAG03	Mode-Analysis Methods for the Study of Collective Instabilities in Electron-Storage Rings	cavity, damping, impedance, simulation	30
	M. Venturini LBNL, Berkeley, California, USA
	We report on recent progress on the application of mode analysis to the study of collective instabilities in electron storage rings including Higher Harmonic RF Cavities (HHCs). The focus is on transverse instabilities in the presence of a dominant resistive-wall impedance, a problem of particular relevance to the new generation of diffraction-limited light sources. The secular equation for the system eigenvalues is solved after applying a regularizing transformation, a key step to obtaining numerically accurate solutions. We provide a demonstration that for vanishing chromaticity and in the absence of radiation damping the beam motion is always unstable. This is in contrast to the more conventional Transverse-Mode-Coupling Instability (TMCI) without HHCs, which is known to exhibit a well defined instability threshold.
	Slides SAPAG03 [2.261 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-SAPAG03
About •	paper received ※ 18 October 2018 paper accepted ※ 24 October 2018 issue date ※ 26 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

SUPLG01	Computational Accelerator Physics: On the Road to Exascale	simulation, space-charge, plasma, optics	113
	R.D. Ryne LBNL, Berkeley, USA
	The first conference in what would become the ICAP series was held in 1988. At that time the most powerful computer in the world was a Cray YMP with 8 processors and a peak performance of 2 gigaflops. Today the fastest computer in the world has more than 2 million cores and a theoretical peak performance of nearly 200 petaflops. Compared to 1988, performance has increased by a factor of 100 million, accompanied by huge advances in memory, networking, big data management and analytics. By the time of the next ICAP in 2021 we will be at the dawn of the Exascale era. In this talk I will describe the advances in Computational Accelerator Physics that brought us to this point and describe what to expect in regard to High Performance Computing in the future. This writeup as based on my presentation at ICAP’18 along with some additional comments that I did not include originally due to time constraints.
	Slides SUPLG01 [25.438 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-SUPLG01
About •	paper received ※ 14 November 2018 paper accepted ※ 07 December 2018 issue date ※ 26 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPLG03	Spin Dynamics in Modern Electron Storage Rings: Computational and Theoretical Aspects	polarization, storage-ring, electron, synchrotron	127
	K.A. Heinemann, O. Beznosov, J.A. Ellison UNM, Albuquerque, New Mexico, USA D. Appelö University of Colorado at Boulder, Boulder, USA D.P. Barber DESY, Hamburg, Germany
	Funding: U.S. Department of Energy, Office of Science, Office of High Energy Physics, Award Number DE-SC0018008 In this talk we present some numerical and analytical results from our work on the spin polarization in high energy electron storage rings. Our work is based on the initial value problem of what we call the full Bloch equations (FBEs). The solution of the FBEs is the polarization density which is proportional to the spin angular momentum density per particle in phase space and which determines the polarization vector of the bunch. The FBEs take into account spin diffusion effects and spin-flip effects due to synchrotron radiation including the Sokolov-Ternov effect and its Baier-Katkov generalization. The FBEs were introduced by Derbenev and Kondratenko in 1975 as a generalization of the Baier-Katkov-Strakhovenko equations from a single orbit to the whole phase space. The FBEs are a system of three uncoupled Fokker-Planck equations plus two coupling terms, i.e., the T-BMT term and the Baier-Katkov term. Neglecting the spin flip terms in the FBEs one gets what we call the reduced Bloch equations (RBEs). The RBEs are sufficient for computing the depolarization time. The conventional approach of estimating and optimizing the polarization is not based on the FBEs but on the so-called Derbenev-Kondratenko formulas. However, we believe that the FBEs offer a more complete starting point for very high energy rings like the FCC-ee and CEPC. The issues for very high energy are: (i) Can one get polarization, (ii) are the Derbenev-Kondratenko formulas satisfactory at very high energy? If not, what are the theoretical limits of the polarization? Item (ii) will be addressed both numerically and analytically. Our numerical approach has three parts. Firstly we approximate the FBEs analytically using the method of averaging, resulting in FBEs which allow us to use large time steps (without the averaging the time dependent coefficients of the FBEs would necessitate small time steps). The minimum length of the time interval of interest is of the order of the orbital damping time. Seco
	Slides MOPLG03 [0.465 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-MOPLG03
About •	paper received ※ 20 October 2018 paper accepted ※ 24 October 2018 issue date ※ 26 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPAF04	Spin Dynamics in Modern Electron Storage Rings: Computational Aspects	polarization, electron, storage-ring, coupling	146
	O. Beznosov, J.A. Ellison, K.A. Heinemann UNM, Albuquerque, New Mexico, USA D. Appelö University of Colorado at Boulder, Boulder, USA D.P. Barber DESY, Hamburg, Germany
	Funding: This material is based on work supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics, under Award Number DE-SC0018008. In this talk we present some numerical results from our work on the spin polarization in high energy electron storage rings. The motivation of our work is to understand spin polarization in very high energy rings like the proposed Future Circular Collider* (FCC-ee) and Circular Electron Positron Collider (CEPC). This talk is a supplement to K. Heinemann’s talk and gives further numerical details and results. As discussed in Heinemann’s talk our work is based on the initial value problem of the full Bloch equations* (FBEs) which in turn determines the polarization vector of the bunch. The FBEs take into account spin diffusion effects and spin-flip effects due to synchrotron radiation. The FBEs are a system of three uncoupled Fokker-Planck equations plus coupling terms. Neglecting the spin flip terms in the FBEs one gets the reduced Bloch equations (RBEs) which poses the main computational challenge. Our numerical approach has three parts. Firstly we approximate the FBEs analytically using the method of averaging, resulting in FBEs which allow us to use large time steps (without the averaging the time dependent coefficients of the FBEs would necessitate small time steps). The minimum length of the time interval of interest is of the order of the orbital damping time. Secondly we discretize the averaged FBEs in the phase space variables by applying the pseudospectral method, resulting in a system of linear first-order ODEs in time. The phase space variables come in d pairs of polar coordinates where d = 1, 2, 3 is the number of degrees of freedom allowing for a d-dimensional Fourier expansion. The pseudospectral method is applied by using a Chebychev grid for each radial variable and a uniform Fourier grid for each angle variable. Thirdly we discretize the ODE system by a time stepping scheme. The presence of parabolic terms in the FBEs necessitates implicit time stepping and thus solutions of linear systems of equations. Dealing with 2d + 1 independent variables p * See http://tlep.web.cern.ch See http://cepc.ihep.ac.cn * See http://ipac2018.vrws.de/papers/thpak144.pdf
	Slides MOPAF04 [0.993 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-MOPAF04
About •	paper received ※ 20 October 2018 paper accepted ※ 24 October 2018 issue date ※ 26 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAF01	Upgrade of MAD-X for HL-LHC Project and FCC Studies	coupling, synchrotron, synchrotron-radiation, lattice	165
	L. Deniau, H. Burkhardt, R. De Maria, M. Giovannozzi, J.M. Jowett, A. Latina, T. Persson, F. Schmidt, I.S. Shreyber, P.K. Skowroński CERN, Geneva, Switzerland T.G. Gläßle HIT, Heidelberg, Germany
	The design efforts for the High Luminosity upgrade of the Large Hadron Collider (HL-LHC) and for the FCC-ee project required significant extensions of the MAD-X code widely used for designing and simulating particle accelerators. The modelling of synchrotron radiation effects has recently been reviewed, improved and tested on the lattices of ESRF, LEP and CLIC Final Focus System. The results were cross checked with the codes AT, PLACET, Geant4, and MAD8. The implementation of space charge has been drastically restructured in a modular design. The linear coupling calculation has been completely reviewed and improved, from the theory to the implementation in MAD-X code to ensure its correctness in the presence of strong coupling as in the HL-LHC studies. The slicing module has been generalised to allow for thick slices of bending magnets, quadrupoles and solenoids. The SBEND element has been extended to support difference between bending angle and integrated dipole strength. Patches have been added to the list of supported elements. MAD-X PTC has also been extended to track resonance driving terms along layouts, and to support AC dipoles to simulate beams during optics measurements.
	Slides TUPAF01 [5.986 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAF01
About •	paper received ※ 17 October 2018 paper accepted ※ 24 October 2018 issue date ※ 26 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAF14	Analytical Calculations for Thomson Backscattering Based Light Sources	electron, laser, scattering, HOM	215
	P.I. Volz, A. Meseck HZB, Berlin, Germany
	There is a rising interest in Thomson-backscattering based light sources, as scattering intense laser radiation on MeV electrons produces high energy photons that would require GeV or even TeV electron beams when using conventional undulators or dipoles. Particularly, medium energy high brightness beams delivered by LINACs or Energy Recovery LINACs, such as BERLinPro being built at Helmholtz-Zentrum Berlin, seem suitable for these sources. In order to study the merit of Thomson-backscattering-based light sources, we are developing an analytical code to simulate the characteristics of the Thomson scattered radiation. The code calculates the distribution of scattered radiation depending on the incident angle and polarization of the laser radiation. Also the impact of the incident laser profile and the full 6D bunch profile, including microbunching, are incorporated. The Status of the code and first results will be presented.
	Slides TUPAF14 [3.289 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAF14
About •	paper received ※ 21 October 2018 paper accepted ※ 28 January 2019 issue date ※ 26 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAG17	Beamline Map Computation for Paraxial Optics	FEL, optics, synchrotron, electron	297
	B. Nash, J.P. Edelen, N.B. Goldring, S.D. Webb RadiaSoft LLC, Boulder, Colorado, USA
	Funding: Department of Energy office of Basic energy sciences, DE-SC0018571 Modeling of radiation transport is an important topic tightly coupled to many charged particle dynamics simulations for synchrotron light sources and FEL facilities. The radiation is determined by the electron beam and magnetic field source, and then passes through beamlines with focusing elements, apertures and monochromators, in which one may typically apply the paraxial approximation of small angular deviations from the optical axis. The radiation is then used in a wide range of spectroscopic experiments, or else may be recirculated back to the electron beam source, in the case of an FEL oscillator. The Wigner function representation of electromagnetic wavefronts has been described in the literature and allows a phase space description of the radiation, similar to that used in charged particle dynamics. It can encompass both fully and partially coherent cases, as well as polarization. Here, we describe the calculation of a beamline map that can be applied to the radiation Wigner function, reducing the computation time. We discuss the use of ray tracing and wave optics codes for the map computation and benchmarking. We construct a four crystal 1:1 imaging beamline that could be used for recirculation in an XFEL oscillator, and benchmark the map based results with SRW wavefront simulations.
	Slides TUPAG17 [2.289 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAG17
About •	paper received ※ 19 October 2018 paper accepted ※ 18 December 2018 issue date ※ 26 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPAG21	Novel, Fast, Open-Source Code for Synchrotron Radiation Computation on Arbitrary 3D Geometries	GPU, undulator, simulation, electron	309
	D.A. Hidas BNL, Upton, Long Island, New York, USA
	Open Source Code for Advanced Radiation Simulation (OSCARS) is an open-source project (https://oscars.bnl.gov) developed at Brookhaven National Laboratory for the computation of synchrotron radiation from arbitrary charged particle beams in arbitrary and time-dependent mag- netic and electric fields on arbitrary geometries in 3D. Computational speed is significantly increased with the use of built-in multi-GPU and multi-threaded techniques which are suitable for both small scale and large scale computing infrastructures. OSCARS is capable of computing spectra, flux, and power densities on simple surfaces as well as on objects imported from common CAD software. It is additionally applicable in the regime of high-field acceleration. The methodology behind OSCARS cal- culations will be discussed along with practical examples and applications to modern accelerators and light sources.
	Slides TUPAG21 [1.712 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAG21
About •	paper received ※ 20 October 2018 paper accepted ※ 18 December 2018 issue date ※ 26 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

SAPAG03

Mode-Analysis Methods for the Study of Collective Instabilities in Electron-Storage Rings

cavity, damping, impedance, simulation

30

M. Venturini
LBNL, Berkeley, California, USA

We report on recent progress on the application of mode analysis to the study of collective instabilities in electron storage rings including Higher Harmonic RF Cavities (HHCs). The focus is on transverse instabilities in the presence of a dominant resistive-wall impedance, a problem of particular relevance to the new generation of diffraction-limited light sources. The secular equation for the system eigenvalues is solved after applying a regularizing transformation, a key step to obtaining numerically accurate solutions. We provide a demonstration that for vanishing chromaticity and in the absence of radiation damping the beam motion is always unstable. This is in contrast to the more conventional Transverse-Mode-Coupling Instability (TMCI) without HHCs, which is known to exhibit a well defined instability threshold.

Slides SAPAG03 [2.261 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-SAPAG03

About •

paper received ※ 18 October 2018 paper accepted ※ 24 October 2018 issue date ※ 26 January 2019

Export •

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

SUPLG01

Computational Accelerator Physics: On the Road to Exascale

simulation, space-charge, plasma, optics

113

R.D. Ryne
LBNL, Berkeley, USA

The first conference in what would become the ICAP series was held in 1988. At that time the most powerful computer in the world was a Cray YMP with 8 processors and a peak performance of 2 gigaflops. Today the fastest computer in the world has more than 2 million cores and a theoretical peak performance of nearly 200 petaflops. Compared to 1988, performance has increased by a factor of 100 million, accompanied by huge advances in memory, networking, big data management and analytics. By the time of the next ICAP in 2021 we will be at the dawn of the Exascale era. In this talk I will describe the advances in Computational Accelerator Physics that brought us to this point and describe what to expect in regard to High Performance Computing in the future. This writeup as based on my presentation at ICAP’18 along with some additional comments that I did not include originally due to time constraints.

Slides SUPLG01 [25.438 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-SUPLG01

About •

paper received ※ 14 November 2018 paper accepted ※ 07 December 2018 issue date ※ 26 January 2019

Export •

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

MOPLG03

Spin Dynamics in Modern Electron Storage Rings: Computational and Theoretical Aspects

polarization, storage-ring, electron, synchrotron

127

K.A. Heinemann, O. Beznosov, J.A. Ellison
UNM, Albuquerque, New Mexico, USA
D. Appelö
University of Colorado at Boulder, Boulder, USA
D.P. Barber
DESY, Hamburg, Germany

Funding: U.S. Department of Energy, Office of Science, Office of High Energy Physics, Award Number DE-SC0018008
In this talk we present some numerical and analytical results from our work on the spin polarization in high energy electron storage rings. Our work is based on the initial value problem of what we call the full Bloch equations (FBEs). The solution of the FBEs is the polarization density which is proportional to the spin angular momentum density per particle in phase space and which determines the polarization vector of the bunch. The FBEs take into account spin diffusion effects and spin-flip effects due to synchrotron radiation including the Sokolov-Ternov effect and its Baier-Katkov generalization. The FBEs were introduced by Derbenev and Kondratenko in 1975 as a generalization of the Baier-Katkov-Strakhovenko equations from a single orbit to the whole phase space. The FBEs are a system of three uncoupled Fokker-Planck equations plus two coupling terms, i.e., the T-BMT term and the Baier-Katkov term. Neglecting the spin flip terms in the FBEs one gets what we call the reduced Bloch equations (RBEs). The RBEs are sufficient for computing the depolarization time. The conventional approach of estimating and optimizing the polarization is not based on the FBEs but on the so-called Derbenev-Kondratenko formulas. However, we believe that the FBEs offer a more complete starting point for very high energy rings like the FCC-ee and CEPC. The issues for very high energy are: (i) Can one get polarization, (ii) are the Derbenev-Kondratenko formulas satisfactory at very high energy? If not, what are the theoretical limits of the polarization? Item (ii) will be addressed both numerically and analytically. Our numerical approach has three parts. Firstly we approximate the FBEs analytically using the method of averaging, resulting in FBEs which allow us to use large time steps (without the averaging the time dependent coefficients of the FBEs would necessitate small time steps). The minimum length of the time interval of interest is of the order of the orbital damping time. Seco

Slides MOPLG03 [0.465 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-MOPLG03

About •

paper received ※ 20 October 2018 paper accepted ※ 24 October 2018 issue date ※ 26 January 2019

Export •

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

MOPAF04

Spin Dynamics in Modern Electron Storage Rings: Computational Aspects

polarization, electron, storage-ring, coupling

146

O. Beznosov, J.A. Ellison, K.A. Heinemann
UNM, Albuquerque, New Mexico, USA
D. Appelö
University of Colorado at Boulder, Boulder, USA
D.P. Barber
DESY, Hamburg, Germany

Funding: This material is based on work supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics, under Award Number DE-SC0018008.
In this talk we present some numerical results from our work on the spin polarization in high energy electron storage rings. The motivation of our work is to understand spin polarization in very high energy rings like the proposed Future Circular Collider* (FCC-ee) and Circular Electron Positron Collider** (CEPC). This talk is a supplement to K. Heinemann’s talk and gives further numerical details and results. As discussed in Heinemann’s talk our work is based on the initial value problem of the full Bloch equations*** (FBEs) which in turn determines the polarization vector of the bunch. The FBEs take into account spin diffusion effects and spin-flip effects due to synchrotron radiation. The FBEs are a system of three uncoupled Fokker-Planck equations plus coupling terms. Neglecting the spin flip terms in the FBEs one gets the reduced Bloch equations (RBEs) which poses the main computational challenge. Our numerical approach has three parts. Firstly we approximate the FBEs analytically using the method of averaging, resulting in FBEs which allow us to use large time steps (without the averaging the time dependent coefficients of the FBEs would necessitate small time steps). The minimum length of the time interval of interest is of the order of the orbital damping time. Secondly we discretize the averaged FBEs in the phase space variables by applying the pseudospectral method, resulting in a system of linear first-order ODEs in time. The phase space variables come in d pairs of polar coordinates where d = 1, 2, 3 is the number of degrees of freedom allowing for a d-dimensional Fourier expansion. The pseudospectral method is applied by using a Chebychev grid for each radial variable and a uniform Fourier grid for each angle variable. Thirdly we discretize the ODE system by a time stepping scheme. The presence of parabolic terms in the FBEs necessitates implicit time stepping and thus solutions of linear systems of equations. Dealing with 2d + 1 independent variables p
* See http://tlep.web.cern.ch
** See http://cepc.ihep.ac.cn
*** See http://ipac2018.vrws.de/papers/thpak144.pdf

Slides MOPAF04 [0.993 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-MOPAF04

About •

paper received ※ 20 October 2018 paper accepted ※ 24 October 2018 issue date ※ 26 January 2019

Export •

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

TUPAF01

Upgrade of MAD-X for HL-LHC Project and FCC Studies

coupling, synchrotron, synchrotron-radiation, lattice

165

L. Deniau, H. Burkhardt, R. De Maria, M. Giovannozzi, J.M. Jowett, A. Latina, T. Persson, F. Schmidt, I.S. Shreyber, P.K. Skowroński
CERN, Geneva, Switzerland
T.G. Gläßle
HIT, Heidelberg, Germany

The design efforts for the High Luminosity upgrade of the Large Hadron Collider (HL-LHC) and for the FCC-ee project required significant extensions of the MAD-X code widely used for designing and simulating particle accelerators. The modelling of synchrotron radiation effects has recently been reviewed, improved and tested on the lattices of ESRF, LEP and CLIC Final Focus System. The results were cross checked with the codes AT, PLACET, Geant4, and MAD8. The implementation of space charge has been drastically restructured in a modular design. The linear coupling calculation has been completely reviewed and improved, from the theory to the implementation in MAD-X code to ensure its correctness in the presence of strong coupling as in the HL-LHC studies. The slicing module has been generalised to allow for thick slices of bending magnets, quadrupoles and solenoids. The SBEND element has been extended to support difference between bending angle and integrated dipole strength. Patches have been added to the list of supported elements. MAD-X PTC has also been extended to track resonance driving terms along layouts, and to support AC dipoles to simulate beams during optics measurements.

Slides TUPAF01 [5.986 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAF01

About •

paper received ※ 17 October 2018 paper accepted ※ 24 October 2018 issue date ※ 26 January 2019

Export •

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

TUPAF14

Analytical Calculations for Thomson Backscattering Based Light Sources

electron, laser, scattering, HOM

215

P.I. Volz, A. Meseck
HZB, Berlin, Germany

There is a rising interest in Thomson-backscattering based light sources, as scattering intense laser radiation on MeV electrons produces high energy photons that would require GeV or even TeV electron beams when using conventional undulators or dipoles. Particularly, medium energy high brightness beams delivered by LINACs or Energy Recovery LINACs, such as BERLinPro being built at Helmholtz-Zentrum Berlin, seem suitable for these sources. In order to study the merit of Thomson-backscattering-based light sources, we are developing an analytical code to simulate the characteristics of the Thomson scattered radiation. The code calculates the distribution of scattered radiation depending on the incident angle and polarization of the laser radiation. Also the impact of the incident laser profile and the full 6D bunch profile, including microbunching, are incorporated. The Status of the code and first results will be presented.

Slides TUPAF14 [3.289 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAF14

About •

paper received ※ 21 October 2018 paper accepted ※ 28 January 2019 issue date ※ 26 January 2019

Export •

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

TUPAG17

Beamline Map Computation for Paraxial Optics

FEL, optics, synchrotron, electron

297

B. Nash, J.P. Edelen, N.B. Goldring, S.D. Webb
RadiaSoft LLC, Boulder, Colorado, USA

Funding: Department of Energy office of Basic energy sciences, DE-SC0018571
Modeling of radiation transport is an important topic tightly coupled to many charged particle dynamics simulations for synchrotron light sources and FEL facilities. The radiation is determined by the electron beam and magnetic field source, and then passes through beamlines with focusing elements, apertures and monochromators, in which one may typically apply the paraxial approximation of small angular deviations from the optical axis. The radiation is then used in a wide range of spectroscopic experiments, or else may be recirculated back to the electron beam source, in the case of an FEL oscillator. The Wigner function representation of electromagnetic wavefronts has been described in the literature and allows a phase space description of the radiation, similar to that used in charged particle dynamics. It can encompass both fully and partially coherent cases, as well as polarization. Here, we describe the calculation of a beamline map that can be applied to the radiation Wigner function, reducing the computation time. We discuss the use of ray tracing and wave optics codes for the map computation and benchmarking. We construct a four crystal 1:1 imaging beamline that could be used for recirculation in an XFEL oscillator, and benchmark the map based results with SRW wavefront simulations.

Slides TUPAG17 [2.289 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAG17

About •

paper received ※ 19 October 2018 paper accepted ※ 18 December 2018 issue date ※ 26 January 2019

Export •

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

TUPAG21

Novel, Fast, Open-Source Code for Synchrotron Radiation Computation on Arbitrary 3D Geometries

GPU, undulator, simulation, electron

309

D.A. Hidas
BNL, Upton, Long Island, New York, USA

Open Source Code for Advanced Radiation Simulation (OSCARS) is an open-source project (https://oscars.bnl.gov) developed at Brookhaven National Laboratory for the computation of synchrotron radiation from arbitrary charged particle beams in arbitrary and time-dependent mag- netic and electric fields on arbitrary geometries in 3D. Computational speed is significantly increased with the use of built-in multi-GPU and multi-threaded techniques which are suitable for both small scale and large scale computing infrastructures. OSCARS is capable of computing spectra, flux, and power densities on simple surfaces as well as on objects imported from common CAD software. It is additionally applicable in the regime of high-field acceleration. The methodology behind OSCARS cal- culations will be discussed along with practical examples and applications to modern accelerators and light sources.

Slides TUPAG21 [1.712 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-ICAP2018-TUPAG21

About •

paper received ※ 20 October 2018 paper accepted ※ 18 December 2018 issue date ※ 26 January 2019

Export •

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