FLS2023 - List of Authors (Tang, C.-X.)

Paper	Title	Page
TU1B2	Low-alpha Storage Ring Design for Steady-State Microbunching to Generate EUV Radiation
	Z. Pan, A. Chao, X.J. Deng, W.-H. Huang, R.K. Li, Z.Z. Li, C.-X. Tang TUB, Beijing, People’s Republic of China
	A new concept is proposed for minimizing the longitudinal emittance of a low momentum compaction factor (low-alpha) storage ring which has the capability to stably store sub-femtosecond electron bunches for the first time. This storage ring is designed for Steady-State microbunching (SSMB) to generate kW level average power EUV radiation. The proposed design approach can be applied to any quasi-isochronous storage rings to yield very high radiation power due to longitudinal coherence of the radiation. We obtain an optimal lattice design by minimizing global and local momentum compaction factors simultaneously and the result of single-particle tracking shows that the electron beam with equilibrium rms bunch length of about 40 nm can be stored in this ring. We also clarify in this type ring, the horizontal emittance will be fixed when beam energy, dipole bending angle and cell tune is fixed. In this type ring, the calculation for IBS effect will be different with traditional rings, we point out where the difference is and give a more convenient calculation for it.
	Slides TU1B2 [1.628 MB]
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TU4P28	Useful Formulas and Example Parameters Set for the Design of SSMB Storage Rings	135
	X.J. Deng, A. Chao, W.-H. Huang, Z.Z. Li, Z. Pan, C.-X. Tang TUB, Beijing, People’s Republic of China
	A promising accelerator light source mechanism called steady-state microbunching (SSMB) has been actively studied in recent years. Here we summarize some important formulas for the design of SSMB storage rings. Generally we group our formulas into two categories, i.e., a longitudinal weak focusing storage ring for a desired radiation wavelength larger than 100 nm, and a transverse-longitudinal coupling, or a generalized longitudinal strong focusing, storage ring for a desired radiation wavelength between 1 nm and 100 nm. In each category, we have presented an example parameters set for the corresponding SSMB storage ring, to generate kW-level infrared, EUV and soft X-ray radiation, respectively.
DOI •	reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P28
About •	Received ※ 15 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023
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TH4D2	An Ultra-high Vacuum, High-gradient RF Gun and Advanced Photocathode Studies
	R.K. Li, H.B. Chen, Y.C. Du, P.W. Huang, W.-H. Huang, J.R. Shi, C.-X. Tang, X.-Y. Zhang, L.M. Zheng TUB, Beijing, People’s Republic of China
	Funding: Work supported by the National Key Research and Development Program of China No. 2022YFA1603400 and the Tsinghua University Initiative Scientific Research Program No. 20197050028, 20191081195. Photoinjectors are critical in defining the beam brightness and lasing performance of linac-based light sources. To further improve photoinjectors, one of the promising R&D opportunities is to combine high acceleration gradient with advanced photocathodes that feature low MTE, high QE, and visible light excitation, but unfortunately stringent vacuum conditions. Here we report on developing a new type of high-gradient S-band photocathode rf gun that can achieve one order of magnitude improvement of the vacuum level at the cathode and thus utilize various advanced semiconductor photocathodes. This gun serves as a testbed for exploring high-gradient-compatible photocathodes and new paradigms for optimizing and operating photoinjectors that enhance future light sources.
	Slides TH4D2 [10.709 MB]
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Paper

Title

Page

TU1B2

Low-alpha Storage Ring Design for Steady-State Microbunching to Generate EUV Radiation

Z. Pan, A. Chao, X.J. Deng, W.-H. Huang, R.K. Li, Z.Z. Li, C.-X. Tang
TUB, Beijing, People’s Republic of China

A new concept is proposed for minimizing the longitudinal emittance of a low momentum compaction factor (low-alpha) storage ring which has the capability to stably store sub-femtosecond electron bunches for the first time. This storage ring is designed for Steady-State microbunching (SSMB) to generate kW level average power EUV radiation. The proposed design approach can be applied to any quasi-isochronous storage rings to yield very high radiation power due to longitudinal coherence of the radiation. We obtain an optimal lattice design by minimizing global and local momentum compaction factors simultaneously and the result of single-particle tracking shows that the electron beam with equilibrium rms bunch length of about 40 nm can be stored in this ring. We also clarify in this type ring, the horizontal emittance will be fixed when beam energy, dipole bending angle and cell tune is fixed. In this type ring, the calculation for IBS effect will be different with traditional rings, we point out where the difference is and give a more convenient calculation for it.

Slides TU1B2 [1.628 MB]

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

TU4P28

Useful Formulas and Example Parameters Set for the Design of SSMB Storage Rings

135

X.J. Deng, A. Chao, W.-H. Huang, Z.Z. Li, Z. Pan, C.-X. Tang
TUB, Beijing, People’s Republic of China

A promising accelerator light source mechanism called steady-state microbunching (SSMB) has been actively studied in recent years. Here we summarize some important formulas for the design of SSMB storage rings. Generally we group our formulas into two categories, i.e., a longitudinal weak focusing storage ring for a desired radiation wavelength larger than 100 nm, and a transverse-longitudinal coupling, or a generalized longitudinal strong focusing, storage ring for a desired radiation wavelength between 1 nm and 100 nm. In each category, we have presented an example parameters set for the corresponding SSMB storage ring, to generate kW-level infrared, EUV and soft X-ray radiation, respectively.

DOI •

reference for this paper ※ doi:10.18429/JACoW-FLS2023-TU4P28

About •

Received ※ 15 August 2023 — Revised ※ 24 August 2023 — Accepted ※ 30 August 2023 — Issued ※ 02 December 2023

Cite •

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

TH4D2

An Ultra-high Vacuum, High-gradient RF Gun and Advanced Photocathode Studies

R.K. Li, H.B. Chen, Y.C. Du, P.W. Huang, W.-H. Huang, J.R. Shi, C.-X. Tang, X.-Y. Zhang, L.M. Zheng
TUB, Beijing, People’s Republic of China

Funding: Work supported by the National Key Research and Development Program of China No. 2022YFA1603400 and the Tsinghua University Initiative Scientific Research Program No. 20197050028, 20191081195.
Photoinjectors are critical in defining the beam brightness and lasing performance of linac-based light sources. To further improve photoinjectors, one of the promising R&D opportunities is to combine high acceleration gradient with advanced photocathodes that feature low MTE, high QE, and visible light excitation, but unfortunately stringent vacuum conditions. Here we report on developing a new type of high-gradient S-band photocathode rf gun that can achieve one order of magnitude improvement of the vacuum level at the cathode and thus utilize various advanced semiconductor photocathodes. This gun serves as a testbed for exploring high-gradient-compatible photocathodes and new paradigms for optimizing and operating photoinjectors that enhance future light sources.

Slides TH4D2 [10.709 MB]

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