Quantitative monitoring of the stripper foil degradation in the 3-GeV rapid cycling synchrotron of the Japan proton accelerator research complex

J-PARC 3GeVシンクロトロンにおける荷電変換フォイルの劣化過程の定量的計測

Saha, P. K.   ; 吉本 政弘  ; 山崎 良雄 ; 發知 英明  ; 原田 寛之  ; 林 直樹  ; 山本 風海   ; 金正 倫計  ; 入江 吉郎*

Saha, P. K.; Yoshimoto, Masahiro; Yamazaki, Yoshio; Hotchi, Hideaki; Harada, Hiroyuki; Hayashi, Naoki; Yamamoto, Kazami; Kinsho, Michikazu; Irie, Yoshiro*

The 3-GeV RCS of the J-PARC requires a long lifetime stripper foil in order to ensure a stable operation. A sudden failure of the foil breaks the accelerator availability as well as raised maintenance issues. A foil degradation (such as foil thinning, pinhole formation) could be a signal of the foil breaking. An efficient monitoring system is needed in order to determine a proper lifetime of a foil for the RCS 1 MW operation so as to avoid any sudden foil failure. During the past 4 months operation of the RCS with about 200 kW beam power to the MLF and nearly 300 kW equivalent beam power to the MR, a single foil was used but there was no observable degradation so far.