Ionization of argon, neon and helium by various alkali ions

Caesium, rubidium, potassium, and sodium positive ions from Kunsman catalyst sources, and lithium ions from spodumene have been used to produce ionization in helium, neon, and argon. In most cases the ionization sets in between 100-150 volts and increases linearly to 750 volts, the highest potential used. Maximum ionization was produced in each gas by the alkali ion closest to it in atomic number.