Temperature Determination on a 9.2 MHz Inductively Coupled Plasma Source Using N2+ Bands as Monitor

Abstract
In recent experiments with a 9.2 MHz inductively coupled plasma assembly air was used as cooling gas. The molecular N2+ band system appeared on the photographic plates taken in the first order of a 3.4 m Jarrell-Ash Ebert grating spectrograph. The rotational lines of this band system was used to evaluate the temperature of the plasma tail flame at various heights above the load coil. These varied from approximately 8000°K at 17 mm above the coil to 6400 at 41 mm.