The study of discharge characteristic of the cold-cathode negative hydrogen PIG-type ion source

The cold-cathode Penning ion gage (PIG)-type ion source is designed for the internal ion source of the compact cyclotron. This kind of ion source has been used for generation of the negative hydrogen (H−) ions for many decades. The discharge characteristics of the ion source are investigated systematically for hydrogen operation at different discharge currents, gas flow rates and magnetic fields, respectively. In this paper, optical emission spectroscopy measurement is carried out to diagnose the parameters of the hydrogen plasma in the ion source. The preliminary optimization of the H− formation with the gas flow rates is discussed and analyzed. Current experimental results can provide useful information for the design and operation of the negative ion source.