Optimization for the additional collimation system of J-PARC RCS

Kato, Shinichi*; Yamamoto, Kazami   ; Yamazaki, Yoshio ; Yoshimoto, Masahiro  ; Kamiya, Junichiro   ; Harada, Hiroyuki  ; Kinsho, Michikazu  

In the J-PARC RCS, the significant losses were observed at the branch of H0 dump line and the Beam Position Monitor which was put at the downstream of the H0 dump branch duct. These losses were caused by the large angle scattering of the injection and circulating beam at the charge exchange foil. To realize high power operation, we have to mitigate these losses. So, we started to develop a new collimation system in the H0 branch duct. In order to optimize this system efficiently, we primarily focused on the relative angle of collimator block from scattering particles. We simulated behavior of particles scattered by foil and produced by collimator block and researched most optimized position and angle of the collimator block. These simulation were performed by SAD and GEANT4. We present simulation results and anticipated performance of this new collimation system.