Nuclear Science and Techniques

《核技术》(英文版) ISSN 1001-8042 CN 31-1559/TL     2019 Impact factor 1.556

Nuclear Science and Techniques ›› 2017, Vol. 28 ›› Issue (7): 90 doi: 10.1007/s41365-017-0242-7


Wakefields studies for the SXFEL user facility

Ming-Hao Song1,2, Chao Feng1, Da-Zhang Huang1, Hai-Xiao Deng1, Bo Liu1, Dong Wang1   

  1. 1 Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Zhangjiang Campus, Shanghai 201204, China
    2 University of Chinese Academy of Sciences, Beijing 100049, China
  • Supported by:

    Supported by the National Natural Science Foundation of China (Nos. 11475250 and 11322550) and Ten Thousand Talent Program.

Ming-Hao Song, Chao Feng, Da-Zhang Huang, Hai-Xiao Deng, Bo Liu, Dong Wang. Wakefields studies for the SXFEL user facility.Nuclear Science and Techniques, 2017, 28(7): 90     doi: 10.1007/s41365-017-0242-7


Besides the original seeded undulator line, in the soft X-ray free-electron laser (SXFEL) user facility in Shanghai, a second undulator line based on self-amplified
spontaneous emission is proposed to achieve 2-nm laser pulse with extremely high brightness. In this paper, the beam energy deviation induced by the undulator wakefields is numerically calculated, and 3D and 2D results agree well with each other. The beam energy loss along the undulator degrades the expected FEL output performances, i.e., the pulse energy, radiation power and spectrum, which can be compensated with a proper taper in the undulator. Using the planned time-resolved diagnostic, a novel experiment is proposed to measure the SXFEL longitudinal wakefields.

Key words: SXFEL, Wakefields, Pulse energy, Radiation power, Spectrum, Taper