Simulation and Optimization of Electron Bunches Transport in an Alpha Magnet Model

ZHU Yunliang; CAO Shuchun; YUAN Ping; ZHANG Jingjing; SHEN Xiaokang; ZHANG Zimin

doi:10.11804/NuclPhysRev.36.03.329

Thermionic RF gun-based electron accelerators can produce ultrashort electron beams. The alpha magnet is used for bunch compression. The transmission process of electron bunch in the alpha magnet is complicated. The research results described in the related literature were based on the ideal model, and the study of beam transmission in an alpha magnet which have an entrance hole in the mirror plate was important for the use of alpha magnet. The design model of alpha magnet is presented, which is the important part of high energy electron radiography facility. The beam transport properties between the ideal model and the alpha magnet are compared by beam dynamics simulation. It is verified that the designed alpha magnet model can effectively compress the electron bunch length. The beam dynamics under the optimization injection angle and space charge effects was discussed. It was found that the effects of the mirror plate entrance hole can be compensated by reducing the injection angle. The multi-bunch simulation results were also reported. The beam emittances and bunch sizes can be optimized by installing some quadrupole magnets between the thermionic RF gun and the alpha magnet.

Simulation and Optimization of Electron Bunches Transport in an Alpha Magnet Model

1. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;

2. School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China

Funds: National Natural Science Foundation of China (11435015); International S&T Cooperation Program of China (2016YFE0104900); Instrument Developing Project of Chinese Academy of Sciences (28Y740010); Natural Science Foundation for Young Scientists of Gansu Province (18JR3RA379)

Received Date: 2018-10-26

Rev Recd Date: 2019-01-16

Publish Date: 2019-09-20

Key words:

Abstract: Thermionic RF gun-based electron accelerators can produce ultrashort electron beams. The alpha magnet is used for bunch compression. The transmission process of electron bunch in the alpha magnet is complicated. The research results described in the related literature were based on the ideal model, and the study of beam transmission in an alpha magnet which have an entrance hole in the mirror plate was important for the use of alpha magnet. The design model of alpha magnet is presented, which is the important part of high energy electron radiography facility. The beam transport properties between the ideal model and the alpha magnet are compared by beam dynamics simulation. It is verified that the designed alpha magnet model can effectively compress the electron bunch length. The beam dynamics under the optimization injection angle and space charge effects was discussed. It was found that the effects of the mirror plate entrance hole can be compensated by reducing the injection angle. The multi-bunch simulation results were also reported. The beam emittances and bunch sizes can be optimized by installing some quadrupole magnets between the thermionic RF gun and the alpha magnet.

HTML

Reference (16)

[1]	KUNG P, LIHN H C, WIEDEMANN H, et al. Phys Rev Lett, 1994, 73(7):967.
[2]	MADEY J M J. Journal of Applied Physics, 1971, 42(5):1906.
[3]	WINICK H, BANE K, BOYCE R, et al. Nucl Instr and Meth A, 1994, 347(1-3):199.
[4]	WIEDEMANN H, BOCEK D, HERNANDEZ M, et al. Journal of Nuclear Materials, 1997, 248(1):374.
[5]	ENGE H A. Review of Scientific Instruments, 1963, 34(4):385.
[6]	BORLAND M, GREEN M C, MILLER R H, et al. Performance of the 2 MeV Microwave Gun for the SSRL 150 MeV LINAC[C]//Proceedings of Linear Accelerator Conference 1990. Nantwich:JP Scientific Ltd, 2013:761.
[7]	LIU Hongxiu. Nucl Instr and Meth A, 1990, 294(1):365.
[8]	HUANG Yongzhang, WU Gang, ZHANG Lingyi, et al. High Power Laser and Particle Beams, 1995, 7(3):354. (in Chinese) (黄永章, 吴钢, 张令翊, 等. 强激光与粒子束, 1995, 7(3):354.)
[9]	BORLAND M. A High-brightness Thermionic Microwave Electron Gun[D]. California:Stanford University, 1991:385.
[10]	BORLAND M. Elegant:a Flexible SDDS-compliant Code for Accelerator Simulation, Advanced Photon Source Light Source Note LS-287, 2000.
[11]	HAMA H, HINODE F, KASAMSOOK K, et al. Space Charge Effect for Short Electron Bunches in an Alpha Magnet[C]//Proceeding of FEL08 Korea:Pohang Accelerator Laboratory, 2009:305.
[12]	VANDER GEER S B, DE LOOS M J. General Particle Tracer User Manual Version 3.35[M]. Netherlands:Pulsar Physics, 2018.
[13]	ZHAO Quantang, CAO Shuchun, LIU Ming, et al. Nucl Instr and Meth A 2016, 832(1):144.
[14]	XIAO Xiaoguang, HU Kesong, LI Zhenghong, et al. High Power Laser and Particle Beams, 2003, 15(8):817. (in Chinese) (肖效光, 胡克松, 李正红, 等. 强激光与粒子束, 2003, 15(8):817.)
[15]	HUANG Yongzhang, TENG Kejian, XIE Jialin. High Energy Physics and Nuclear Physics, 1993, 17(9):790. (in Chinese) (黄永章, 腾可俭, 谢家麟. 高能物理与核物理, 1993, 17(9):790.)
[16]	ZHU Yunliang, YUAN Ping, CAO Shuchun, et al. Nucl Instr and Meth A, 2018, 911(1):74.

Simulation and Optimization of Electron Bunches Transport in an Alpha Magnet Model

doi: 10.11804/NuclPhysRev.36.03.329

Abstract

References

Proportional views

通讯作者: 陈斌, bchen63@163.com

Article Metrics

Proportional views