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 ›› 2020, Vol. 31 ›› Issue (7): 73 doi: 10.1007/s41365-020-00772-z


RF design optimization for the SHINE 3.9 GHz cavity

Yu-Xin Zhang1, 2 Jin-Fang Chen1,3 Dong Wang1,3   

  1. 1Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China
    2ShanghaiTech University, Shanghai 201210, China
    3Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
  • Received:2020-01-02 Revised:2020-04-17 Accepted:2020-04-21
  • Contact: Jin-Fang Chen E-mail:
  • Supported by:
    This work was partially supported by the National Key Research and De- velopment Program of China (No. 2016YFA0401900) and the Shanghai Municipal Science and Technology Major Project (No. 2017SHZDZX02).
PDF ShareIt Export Citation
Yu-Xin Zhang, Jin-Fang Chen, Dong Wang. RF design optimization for the SHINE 3.9 GHz cavity.Nuclear Science and Techniques, 2020, 31(7): 73     doi: 10.1007/s41365-020-00772-z

Abstract: The Shanghai High-repetition-rate XFEL and Extreme Light Facility (SHINE) under construction is designed to be one of the most advanced free electron laser (FEL) facilities in the world. The main part of the SHINE facility is an 8 GeV superconducting Linac operating in continuous wave (CW) mode. The Linac consists of seventy-five 1.3 GHz and two 3.9 GHz cryomodules. Based on the design and experience of 3.9 GHz cavities in the European X-ray Free Electron Laser (E-XFEL) and the Linac Coherent Light Source-II (LCLS-II) projects, we optimize the SHINE 3.9 GHz cavity design to adapt it for CW mode operation. In this paper, we present a particular redesign of the end-group for the SHINE 3.9 GHz superconducting cavity that includes a redesign of the end-cell and beam pipe to shift away the potentially troublesome lowest high order modes(HOMs), a modification of the main coupler antenna, and a tuning of the HOM notch filter to meet the cavity requirements. RF losses calculations on the HOM coupler antennas show that the overheating on the inner conductor at the operating mode is diminished significantly. Furthermore, we have also studied the HOMs to ensure there are no dangerously trapped modes in the optimized cavity design.

Key words: Superconducting cavity, Higher order modes, RF design