Abstract
A source is described for the production of negative ions of tungsten and rhenium oxides. Total negative ion currents of 4×10−8 and 1.5×10−8 A were obtained for rhenium and tungsten oxides, respectively, the dominant ions being ReO3 and ReO4 or WO3, (WO3)2, and (WO3)3. Both thermionic emission and hot cathode arc discharges were used as the ion source with the oxides being produced by direct oxidation of the heated cathode.