Determination of the Predominant Ionization and Loss Mechanisms for the Low‐Voltage Arc Mode in a Neon Plasma Diode

Abstract

A reaction‐rate analysis is used to determine the relative importance of the predominant ionization and loss mechanisms in a neon low‐voltage arc. Experimental data are derived from various experiments to determine density, cross section, etc. It is found that the resonance and metastable state atoms are primarily generated in a region near the cathode which corresponds to the ``cathode ball‐of‐fire'' region of the low‐voltage arc. The predominant ion‐generation process is found to be a result of collisions between excited atoms which cause the formation of a molecular ion. Direct ionization of ground‐state atoms is of secondary but non‐negligible, importance. Consideration of quasi‐equilibrium multistage ionization shows that, unlike the cesium low‐voltage arc, it is unimportant in the neon low‐voltage arc. The escape of resonance radiation accounts for approximately one‐fifth of the total power loss while ionization accounts for approximately one‐eighth. Most of the remaining power loss appears as power dissipation at the anode.