FLS2023 - List of Authors (Stupakov, G.)

Paper	Title	Page
TH3D4	DFCSR: A Fast Calculation of 2D/3D Coherent Synchrotron Radiation in Relativistic Beams
	J. Tang, Z. Huang, G. Stupakov SLAC, Menlo Park, California, USA
	Coherent Synchrotron Radiation (CSR) is regarded as one of the most important reasons that limits beam brightness in modern accelerators. Current numerical packages containing CSR wake fields generally use 1D models, which can become invalid in electron beams with very high brightness. On the other hand, the existing 2D or 3D codes are often slow. Here we report DFCSR, a novel particle tracking code that can simulate 2D/3D CSR and space charge wakes in relativistic electron beams 2 or 3 orders of magnitude faster than conventional models like CSRtrack. We performed benchmark simulations based on FACET-II beams, where electron beams are compressed to reach 300 kA peak current. The tracking code is written in Python and C programming languages with human-friendly input styles and is open-sourced on GitHub. It can serve as a powerful simulation tool for the design of next-generation accelerators.
	Slides TH3D4 [2.598 MB]
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TU2A2	Single Longitudinal Mode Generation in Slippage-dominated, Tapered-undulator SASE Soft X-ray FEL	70
	D.C. Nguyen, M. Dunham, W. Lou, C.E. Mayes, G. Stupakov xLight, Palo Alto, USA
	SASE FELs operating in the soft X-ray region exhibit multiple temporal and spectral spikes with an overall spectral bandwidth of about 1.5 times the FEL rho parameter. While many ideas have been proposed to achieve fully coherent X-ray FELs, only monochromatic seeding, either harmonic seeding* or SASE self-seeding*, has been experimentally demonstrated to narrow the output spectra of soft X-ray FELs. In this paper, we study a different method that relies on the Slippage-dominated Tapered Undulator (STU) SASE concept to produce a single longitudinal mode in a soft X-ray FEL driven by ~10-fs, 16-pC electron bunches. We pre-sent numerical simulation results that demonstrate single-mode generation and narrow-lined spectra without seeding in a STU-SASE FEL at 6.67 nm. E. Alaria et al., Nat Photon 7 (2013) 913-918 ** D. Ratner et al., PRL 114 (2015) 050801
	Slides TU2A2 [1.125 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU2A2
About •	Received ※ 22 August 2023 — Revised ※ 23 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

TH3D4

DFCSR: A Fast Calculation of 2D/3D Coherent Synchrotron Radiation in Relativistic Beams

J. Tang, Z. Huang, G. Stupakov
SLAC, Menlo Park, California, USA

Coherent Synchrotron Radiation (CSR) is regarded as one of the most important reasons that limits beam brightness in modern accelerators. Current numerical packages containing CSR wake fields generally use 1D models, which can become invalid in electron beams with very high brightness. On the other hand, the existing 2D or 3D codes are often slow. Here we report DFCSR, a novel particle tracking code that can simulate 2D/3D CSR and space charge wakes in relativistic electron beams 2 or 3 orders of magnitude faster than conventional models like CSRtrack. We performed benchmark simulations based on FACET-II beams, where electron beams are compressed to reach 300 kA peak current. The tracking code is written in Python and C programming languages with human-friendly input styles and is open-sourced on GitHub. It can serve as a powerful simulation tool for the design of next-generation accelerators.

Slides TH3D4 [2.598 MB]

Cite •

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

TU2A2

Single Longitudinal Mode Generation in Slippage-dominated, Tapered-undulator SASE Soft X-ray FEL

70

D.C. Nguyen, M. Dunham, W. Lou, C.E. Mayes, G. Stupakov
xLight, Palo Alto, USA

SASE FELs operating in the soft X-ray region exhibit multiple temporal and spectral spikes with an overall spectral bandwidth of about 1.5 times the FEL rho parameter. While many ideas have been proposed to achieve fully coherent X-ray FELs, only monochromatic seeding, either harmonic seeding* or SASE self-seeding**, has been experimentally demonstrated to narrow the output spectra of soft X-ray FELs. In this paper, we study a different method that relies on the Slippage-dominated Tapered Undulator (STU) SASE concept to produce a single longitudinal mode in a soft X-ray FEL driven by ~10-fs, 16-pC electron bunches. We pre-sent numerical simulation results that demonstrate single-mode generation and narrow-lined spectra without seeding in a STU-SASE FEL at 6.67 nm.
* E. Alaria et al., Nat Photon 7 (2013) 913-918
** D. Ratner et al., PRL 114 (2015) 050801

Slides TU2A2 [1.125 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU2A2

About •

Received ※ 22 August 2023 — Revised ※ 23 August 2023 — Accepted ※ 31 August 2023 — Issued ※ 02 December 2023

Cite •

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