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 ›› 2010, Vol. 21 ›› Issue (3): 134-140 doi: 10.13538/j.1001-8042/nst.21.134-140


Low-alpha optics design for SSRF

WANG Xin1, 2 TIAN Shunqiang1 LIU Guimin1,*   

  1. 1 Shanghai Institute of Applied Physics, Chinese Academy of Science, Shanghai 201800, China 2 Graduate University of Chinese Academy of Science, Beijing 100049, China
WANG Xin, TIAN Shunqiang, LIU Guimin. Low-alpha optics design for SSRF.Nuclear Science and Techniques, 2010, 21(3): 134-140     doi: 10.13538/j.1001-8042/nst.21.134-140


In this paper,short pulse radiation in Shanghai Synchrotron Radiation Facility(SSRF)is generated by the low momentum compaction factor(α_C)optics,and three kinds of the low-α_C optics are found,with the very lowα_C being adopted by reducing dispersion in the straight section to negative value in the SSRF.Energy acceptance is selected as objective functions in nonlinear optimization rather than the second orderα_C or other nonlinear driving terms.The optimal result is improved step-by-step by randomly setting harmonic sextupole strengths.Two optics modes,i.e.low positiveα_C and low negativeα_C,are analyzed.In order to get a large energy acceptance and only one stable point in longitudinal phase space,the low negativeα_C optics is taken as an operation mode for the short pulse radiation in the SSRF.

Key words: SSRF, low-α_C, beam optics design, nonlinear optimization, energy acceptance