NAPAC2022 - List of Authors (Carlsten, B.E.)

Paper	Title	Page
WEZD1	ARDAP’s Perspective on Accelerator Technology R&D in the U.S.	592
	B.E. Carlsten, E.R. Colby, R.A. Marsh, M. White ARDAP, Washington, USA
	DOE operates several particle accelerator facilities and is planning several new forward-leaning accelerator facilities over the next decade or two. These new facilities will focus on discovery science research and fulfilling other core DOE missions. Near and mid-term examples include PIP-II and FACET-II (for High Energy Physics); LCLS-II, SNS-PPU, APS-U, and ALS-U (for Basic Energy Sciences); FRIB (for Nuclear Physics); NSTX-U and MPEX (for Fusion Energy Sciences); and Scorpius (for NNSA). Longer-term examples may include future colliders, the SNS-STS, LCLS-II HE, and EIC. In addition to domestic facilities, DOE’s Office of Science (SC) also contributes to several international efforts. Together, these new facilities constitute a multibillion-dollar construction and operations investment. To be successful, they will require advances in state-of-the-art accelerator technologies. They will also require the National Laboratories to procure a variety of accelerator components. This paper summarizes how DOE is working to address these upcoming R&D and accelerator component production needs through its new office of Accelerator R&D and Production (ARDAP).
	Slides WEZD1 [2.310 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEZD1
About •	Received ※ 05 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 19 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA53	Modeling of Nonlinear Beam Dynamics via a Novel Particle-Mesh Method and Surrogate Models with Symplectic Neural Networks	462
	C.-K. Huang, O. Beznosov, J.W. Burby, B.E. Carlsten, G.A. Dilts, J. Domine, R. Garimella, A. Kim, T.J. Kwan, H.N. Rakotoarivelo, R.W. Robey, B. Shen, Q. Tang LANL, Los Alamos, New Mexico, USA F.Y. Li New Mexico Consortium, Los Alamos, USA
	Funding: Work supported by the LDRD program at Los Alamos National Laboratory and the ASCR SciML program of DOE. The self-consistent nonlinear dynamics of a relativistic charged particle beam, particularly through the interaction with its complete self-fields, is a fundamental problem underpinning many accelerator design issues in high brightness beam applications, as well as the development of advanced accelerators. A novel self-consistent particle-mesh code, CoSyR [1], is developed based on a Lagrangian method for the calculation of the beam particles’ radiation near-fields and associated beam dynamics. Our recent simulations reveal the slice emittance growth in a bend and complex interplay between the longitudinal and transverse dynamics that are not captured in the 1D longitudinal static-state Coherent Synchrotron Radiation (CSR) model. We further show that surrogate models with symplectic neural networks can be trained from simulation data with significant time-savings for the modeling of nonlinear beam dynamics effects. Possibility to extend such surrogate models for the study of spin-orbital coupling is also briefly discussed. [1] C.-K. Huang et al., Nucl. Instruments Methods Phys. Res. Sect. A, vol. 1034, p. 166808, 2022.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA53
About •	Received ※ 25 July 2022 — Revised ※ 03 August 2022 — Accepted ※ 09 August 2022 — Issue date ※ 11 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA73	Design and Low Power Test of an Electron Bunching Enhancer Using Electrostatic Potential Depression	499
	H. Xu, B.E. Carlsten, Q.R. Marksteiner LANL, Los Alamos, New Mexico, USA B.L. Beaudoin, T.W. Koeth, A. Ting UMD, College Park, Maryland, USA
	Funding: This project was supported by the U.S. Department of Energy Office of Science through the Accelerator Stewardship Program. We present our experimental design and low power test results of a structure for the proof-of-principle demonstration of fast increase of the first harmonic current content in a bunched electron beam, using the technique of electrostatic potential depression (EPD). A primarily bunched electron beam from an inductive output tube (IOT) at 710 MHz first enters an idler cavity, where the longitudinal slope of the beam energy distribution is reversed. The beam then transits through an EPD section implemented by a short beam pipe with a negative high voltage bias, inside which the rate of increase of the first harmonic current is significantly enhanced. An output cavity measures the harmonic current developed inside the beam downstream of the EPD section. Low power test results of the idler and the output cavities agree with the theoretical design.
	Poster TUPA73 [1.307 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA73
About •	Received ※ 29 July 2022 — Accepted ※ 03 August 2022 — Issue date ※ 09 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRXD4	Suppressing the Microbunching Instability at ATF using Laser Assisted Bunch Compression	914
	Q.R. Marksteiner, P.M. Anisimov, B.E. Carlsten, G. Latour, E.I. Simakov, H. Xu LANL, Los Alamos, New Mexico, USA
	Funding: This project was supported by funding from the Los Alamos National Laboratory Laboratory Research and Development program. The microbunching instability in linear accelerators can significantly increase the energy spread of an electron beam. The instability can be suppressed by artificially increasing the random energy spread of an electron beam, but this leads to unacceptably high energy spreads for future XFEL systems. One possibility of suppressing this instability is to use laser assisted bunch compression (LABC) instead of the second chicane in an XFEL system, thereby eliminating the cascaded chicane effect that magnifies the microbunching instability. An experiment is proposed at ATF to test this concept, and numerical simulations of the experiment are shown.
	Slides FRXD4 [4.629 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-FRXD4
About •	Received ※ 03 August 2022 — Revised ※ 11 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 28 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

ARDAP’s Perspective on Accelerator Technology R&D in the U.S.

592

B.E. Carlsten, E.R. Colby, R.A. Marsh, M. White
ARDAP, Washington, USA

DOE operates several particle accelerator facilities and is planning several new forward-leaning accelerator facilities over the next decade or two. These new facilities will focus on discovery science research and fulfilling other core DOE missions. Near and mid-term examples include PIP-II and FACET-II (for High Energy Physics); LCLS-II, SNS-PPU, APS-U, and ALS-U (for Basic Energy Sciences); FRIB (for Nuclear Physics); NSTX-U and MPEX (for Fusion Energy Sciences); and Scorpius (for NNSA). Longer-term examples may include future colliders, the SNS-STS, LCLS-II HE, and EIC. In addition to domestic facilities, DOE’s Office of Science (SC) also contributes to several international efforts. Together, these new facilities constitute a multibillion-dollar construction and operations investment. To be successful, they will require advances in state-of-the-art accelerator technologies. They will also require the National Laboratories to procure a variety of accelerator components. This paper summarizes how DOE is working to address these upcoming R&D and accelerator component production needs through its new office of Accelerator R&D and Production (ARDAP).

Slides WEZD1 [2.310 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEZD1

About •

Received ※ 05 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 19 August 2022

Cite •

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

TUPA53

Modeling of Nonlinear Beam Dynamics via a Novel Particle-Mesh Method and Surrogate Models with Symplectic Neural Networks

462

C.-K. Huang, O. Beznosov, J.W. Burby, B.E. Carlsten, G.A. Dilts, J. Domine, R. Garimella, A. Kim, T.J. Kwan, H.N. Rakotoarivelo, R.W. Robey, B. Shen, Q. Tang
LANL, Los Alamos, New Mexico, USA
F.Y. Li
New Mexico Consortium, Los Alamos, USA

Funding: Work supported by the LDRD program at Los Alamos National Laboratory and the ASCR SciML program of DOE.
The self-consistent nonlinear dynamics of a relativistic charged particle beam, particularly through the interaction with its complete self-fields, is a fundamental problem underpinning many accelerator design issues in high brightness beam applications, as well as the development of advanced accelerators. A novel self-consistent particle-mesh code, CoSyR [1], is developed based on a Lagrangian method for the calculation of the beam particles’ radiation near-fields and associated beam dynamics. Our recent simulations reveal the slice emittance growth in a bend and complex interplay between the longitudinal and transverse dynamics that are not captured in the 1D longitudinal static-state Coherent Synchrotron Radiation (CSR) model. We further show that surrogate models with symplectic neural networks can be trained from simulation data with significant time-savings for the modeling of nonlinear beam dynamics effects. Possibility to extend such surrogate models for the study of spin-orbital coupling is also briefly discussed.
[1] C.-K. Huang et al., Nucl. Instruments Methods Phys. Res. Sect. A, vol. 1034, p. 166808, 2022.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA53

About •

Received ※ 25 July 2022 — Revised ※ 03 August 2022 — Accepted ※ 09 August 2022 — Issue date ※ 11 August 2022

Cite •

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

TUPA73

Design and Low Power Test of an Electron Bunching Enhancer Using Electrostatic Potential Depression

499

H. Xu, B.E. Carlsten, Q.R. Marksteiner
LANL, Los Alamos, New Mexico, USA
B.L. Beaudoin, T.W. Koeth, A. Ting
UMD, College Park, Maryland, USA

Funding: This project was supported by the U.S. Department of Energy Office of Science through the Accelerator Stewardship Program.
We present our experimental design and low power test results of a structure for the proof-of-principle demonstration of fast increase of the first harmonic current content in a bunched electron beam, using the technique of electrostatic potential depression (EPD). A primarily bunched electron beam from an inductive output tube (IOT) at 710 MHz first enters an idler cavity, where the longitudinal slope of the beam energy distribution is reversed. The beam then transits through an EPD section implemented by a short beam pipe with a negative high voltage bias, inside which the rate of increase of the first harmonic current is significantly enhanced. An output cavity measures the harmonic current developed inside the beam downstream of the EPD section. Low power test results of the idler and the output cavities agree with the theoretical design.

Poster TUPA73 [1.307 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA73

About •

Received ※ 29 July 2022 — Accepted ※ 03 August 2022 — Issue date ※ 09 August 2022

Cite •

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

FRXD4

Suppressing the Microbunching Instability at ATF using Laser Assisted Bunch Compression

914

Q.R. Marksteiner, P.M. Anisimov, B.E. Carlsten, G. Latour, E.I. Simakov, H. Xu
LANL, Los Alamos, New Mexico, USA

Funding: This project was supported by funding from the Los Alamos National Laboratory Laboratory Research and Development program.
The microbunching instability in linear accelerators can significantly increase the energy spread of an electron beam. The instability can be suppressed by artificially increasing the random energy spread of an electron beam, but this leads to unacceptably high energy spreads for future XFEL systems. One possibility of suppressing this instability is to use laser assisted bunch compression (LABC) instead of the second chicane in an XFEL system, thereby eliminating the cascaded chicane effect that magnifies the microbunching instability. An experiment is proposed at ATF to test this concept, and numerical simulations of the experiment are shown.

Slides FRXD4 [4.629 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-FRXD4

About •

Received ※ 03 August 2022 — Revised ※ 11 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 28 September 2022

Cite •

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