Operation maintenance of the thyratron for the power supply of the extraction kicker magnet in the J-PARC 3GeV RCS

Togashi, Tomohito; Watanabe, Masao  ; Suganuma, Kazuaki ; Takayanagi, Tomohiro   ; Ueno, Tomoaki; Tani, Norio  ; Watanabe, Yasuhiro  ; Kinsho, Michikazu  

The 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex) uses 8 pulse kicker magnets for the beam extraction at a repetition rate of 25 Hz. Each kicker power supply has 2 thyratrons and thus they are 16 in total. An average life time of thyratrons even more than the J-PARC annual operation time of 5000 hours and a stable operation with a downtime of less than only 0.5% has already been achieved. The present maintenance procedures and statistics for the long term operation with thyratrons are reported in this paper.