DEVELOPMENT OF A HIGH-BRIGHTNESS NEGATIVE HYDROGEN-ION SOURCE

A high brightness negative hydrogen ion source has been developed for a high intensity proton linear accelerator. The ion source is volume p roduction type. Negative ions are generated in a magnetically filtered multicusp plasma generator. The negative ion production is enhanced b y seeding a small amount of cesium into the plasma generator. A negati ve hydrogen ion beam of 36 mA was extracted from a single aperture at an acceleration voltage of 50 kV. To obtain a higher ion beam current, the focusing of beamlets extracted from the multiaperture grid has be en demonstrated with an aperture displacement technique. (C) 1996 Amer ican Institute of Physics.