Progress of the J-PARC cesiated RF-driven negative hydrogen ion source

In the 2017/2018 campaign, the J-PARC cesiated rf-driven negative hydrogen (H−) ion source producing H− beam with the beam current of 47 mA accomplished three long-term operations more than 2,000 hours without any serious issues. On the final day of this campaign, the ion source produced an H− beam with the beam current of 72 mA so that the linac commissioning group could demonstrate the H− beam current of 60 mA at the linac exit. We are also conducting an endurance test of a J-PARC-made antenna at a test bench. The antenna achieved the operation time of approximately 1,400 hours.