Estimating cathodic plasma jet parameters from the vacuum arc charge state distribution

Abstract

An analysis of the ion charge distribution measurements in a vacuum arc plasma has been carried out. It has been demonstrated that, by using the Saha equation, one can determine the electron temperature Te and density Ne in the cathode spot plasma. It has also been shown that it is possible to estimate a microspot diameter d and a current density j in the microspot by applying a theoretical model. The values obtained for Te approximately=4-10 eV, Ne approximately=1026-1028 m-3, d approximately=0.2-0.5 mu m and j approximately=(1-30)*1012 A m-2 are in agreement with recent measurements.