Operation status of the J-PARC negative hydrogen ion source

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

The J-PARC ion source has succeeded in providing the required beam to the accelerator for approximately 3.5 years without any serious trouble. At the recent beam run, approximately 600 hours continuous operation was achieved. Although the ion source can produce a maximum beam current of 36 mA, the beam current has been restricted to less than 16 mA for the stable operation of the RFQ linac which has serious discharge problem. After each beam run, we perform the ion source maintenance to replace some elements for the plasma production such as a filament, a plasma chamber and so on. Approximately three days was necessary to accomplish the maintenance. In order to enhance the availability of the accelerator, reduction of the maintenance time is indispensable. At present, we succeed in cutting the maintenance time in half by using the filament pre-baking system. We will make another attempt to shorten the time by unitizing the replacement elements in the near future.