A preliminary study of a negative hydrogen PIG-type ion source for the compact cyclotron

A Penning ion gauge (PIG)-type ion source has been used for the generation of negative hydrogen ions (H-) as the internal ion source of the compact cyclotron. The discharge characteristics of the ion source are systematically studied for hydrogen operation at different discharge currents and gas flow rates on the prototype cyclotron. The preliminary study results for the low DC voltage H- extraction measurements are presented in this paper. The H- beam current is measured by the order of magnitude from several tens to hundreds of microamperes at different parameter conditions. The discussion and analysis for the experimental results are good for improving the design and working stability of the ion source. (authors)