Study of Beam Loss due to Particle Scattering in CSNS/RCS

In the Rapid Cycling Synchrotron of China Spallation Neutron Source (CSNS/RCS), the proton beam will interact with some devices, such as the stripping foil, beam collimator, and foil for scattering extraction. These interactions result in some particle scattering and beam losses. In this paper, firstly, the beam transportation in the injection procedure was simulated by ORBIT and the particle scattering due to the interaction between the beam and stripping foil was simulated by FLUKA, then the beam loss due to the foil scattering was calculated. Secondly, the particle scattering due to the proton beam interacting with the secondary collimator was simulated, and based on which, the secondary collimator was optimized by calculating the absorb efficiency. The optimization was done for the foil scattering extraction scheme by simulating and comparing different schemes with FLUKA.