Measurements of Rotational Temperatures in the Hollow Cathode Discharge

Abstract
Rotational temperatures in the uncooled hollow cathode discharge (HCD) have been measured. Using rotational lines of the OH (0,0) band, the temperatures were measured in a helium fill gas pressure range from 266 to 2130 Pa and in the discharge current between 0.1 and 0.3 A. A comparative study of these temperatures with gas and excitation temperatures in HCD is presented.