Effective improvement of beam lifetime based on radiofrequency phase modulation at the HLS-Ⅱ storage ring

作者:Yun-Kun Zhao; Bao-Gen Sun; Ji-Gang Wang; Fang-Fang Wu; Ping Lu; Tian-Yu Zhou; San-Shuang Jin
来源:Nuclear Science and Techniques, 2021, 32(01): 3-11.

摘要

A radiofrequency(RF) phase modulation method is applied to the Hefei Light Source II storage ring to deeply investigate its longitudinal beam characteristics and improve the beam lifetime.A theoretical analytical model and corresponding experimental measurements of single bunch length and island phenomena are examined.From a series of online machine experiments,we demonstrate that the suitable phase modulation amplitude is 0.02 rad,corresponding to an optimum modulation frequency ranging from 19.6 to 20.7 k Hz of the RF system.Furthermore,the overall beam lifetime can be increased by a factor of 2.38 as a result of the beam dilution effect.