Speaker
Description
For the China Spallation Neutron Source (CSNS), the rapid cycling synchrotron (RCS) accumulates and accelerates the injection beam to the design energy of 1.6 GeV and then extracts the high energy beam to the target. As the second phase of the CSNS, CSNS-II will achieve a beam power on the target of 500 kW. The injection energy of CSNS-II will be increased from 80 MeV to 300 MeV and the injection beam power will be increased about 20 times. In this paper, for the CSNS-II，the upgrade of the RCS will be introduced and studied in detail, including the new injection system, new dual harmonic cavity, main magnet power supplies upgrade, new collimation system, beam instability, space charge effects, and so on. In order to meet the requirements of beam power increase and stable operation, the RCS beam losses from different sources are studied and optimized. Based on the detailed simulation results and beam experimental results, the feasibility upgrade schemes of the critical systems for the CSNS RCS will be given.
