Performance of a low‐duty pulsed Penning source for the medical synchrotron facility at NIRS

A low‐duty pulsed Penning source has been developed for the injector of the medical synchrotron facility at NIRS. The repetition rate is 1 Hz, with a duty factor of 4×10−4. The lifetime of the cathodes has been evaluated to be longer than two months, and that of the filament (cw) longer than one week. The intensity of multiply charged ions was increased by a factor of 10 compared with that obtained under dc operation. The reliability and stability were also improved. The results concerning the performance and some improvements of the source are discussed.