Operation status of the J-PARC negative hydrogen ion source

Oguri, Hidetomo  ; Ikegami, Kiyoshi*; Okoshi, Kiyonori ; Namekawa, Yuya; Ueno, Akira  ; Takagi, Akira*

The availability of the ion source is directly related to the operation time of the J-PARC accelerator. To evaluate the lifetime of the present ion source, we tried to perform two months beam operation in RUN#36. As the result of the trial operation, 1270 h continuous operation was achieved at the beam current of 16 mA. In RUN#37, the ion source was operated at 25 mA for 217 h at first, then the beam current was decreased to 16 mA. After 1029 h operation, the filament of the ion source was cut off and the beam run was interrupted. By considering the consumption rate of the filament is depended on the beam current, these operation results show the lifetime of the ion source is approximately 1200 h. For another attempt to improve the ion source availability, we tried to decrease the required time for maintenance. By unitizing the replacement parts and keeping them under the vacuum condition until just before the installing, the maintenance time can be decreased from four to two days.