Determination of temperature in a radio-frequency discharge using a reversal technique

An absorption technique for determining the temperature in a circularly symmetric discharge has been developed by Elder, Jerrick and Birkeland, and applied by them to a low-temperature discharge using a tungsten ribbon background source. This technique has been extended here to a higher temperature radio-frequency discharge in argon at atmospheric pressure using a condenser discharge background source. The measured off-axis temperature maximum of 9200°K is in agreement with previous measurements. The error introduced by the finite resolution of the spectrograph used is discussed.