The internal Penning Ion Source of negative hydrogen ions for isochronous cyclotrons

The results of an experimental study of the Penning Ion Source (PIS) contained in isochronous cyclotrons are given for two main directions: low and high discharge current. The new effect for generation of negative hydrogen ions with low discharge current was observed and is described in this paper. The high discharge current with rod cathodes is considered for increasing component lifetimes in the internal ion source of the Siemens Eclipse cyclotron.