Frequency range for stable generation of atmospheric glow discharges in helium and nitrogen

Summary form only given, as follows. We aim to study the effects of the temporal characteristics of the excitation on atmospheric plasma dynamics. In particular we establish the frequency range within which stable atmospheric glow discharges can be generated with sinusoidal excitation. We consider both a helium discharge and nitrogen discharge, such that the difference of discharge dynamics in these two different gases is used to probe the physics that underscores their different frequency ranges. Using a theoretical model that has been validated with experiments, atmospheric helium discharges and atmospheric nitrogen discharges are studied in detail. Through numerical examples, their respective frequency ranges for stable generation of atmospheric glow discharges are deduced. The difference in these frequency ranges is discussed from the standpoint of the difference in key ionization processes in these two different carrier gases. These are also compared with experimental results.