Foil scattering loss mitigation by the additional collimation system of J-PARC RCS

Yamamoto, Kazami   ; Yamazaki, Yoshio ; Yoshimoto, Masahiro  ; Kamiya, Junichiro   ; Harada, Hiroyuki  ; Saha, P. K.   ; Hotchi, Hideaki  ; Kinsho, Michikazu  ; Kato, Shinichi*

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. From the beam study, we were certain that these losses were caused by the scattering of the injection and circulating beam at the charge exchange injection foil. In order to mitigate these losses, we started to develop a new collimation system in the H0 branch duct. We present latest study results and overview of this new collimation system.