Incoherent Transverse Tune Shift Caused by Space-charge Effects in HEPS Storage Ring and Booster

Abstract

In cases of low beam energy and high particle densities, space-charge effects become necessary discussions on transverse beam dynamics. It may cause a big enough tune shift in a circular accelerator moving the beam onto a resonance. In this paper, the transverse tune shift in High Energy Photon Source (HEPS) storage ring and booster ring caused by space-charge effects is firstly estimated based on the existing theory. Since the tune shift is at the level of 0.2, it may move the beam onto a resonance in the operation mode with high bunch charges. Then some simulations are made by tracking particles with elegant in the HEPS storage ring and booster including the space-charge effects. During the tracking, some particles are lost in HEPS booster ring with bunch charge of 14.4nC for the so called 'swap-out' mode. Further simulation shows that no particles would be lost if the charge of single bunch was less than 8.6nC in HEPS booster.