Surface Plasma Source Electrode Activation by Surface Impurities...

In experiments with RF saddle antenna surface plasma sources (SPS) , the efficiency of H- ion generation was increased by up to a factor of 5 by long time plasma electrode “activation”, without adding Cs from Cs supply, by heating the collar to high temperature using hot air flow and plasma discharge. Without cracking or heating the cesium ampoule, but likely with Cs recovery from impurities, the achieved energy efficiency was comparable to that of conventionally cesiated SNS RF sources with an external or internal Cs supply. In the experiments, perfect cesiation was produced (without additional Cs supply) by the collection and trapping of traces of remnant cesium compounds from SPS surfaces.