Determination of mean electron energy in an elevated-pressure plasma by the probe method

The possibility of determining mean electron energy from the slope of the dependence of probe electron current on probe potential under conditions of a nonequilibrium electron energy distribution function (EEDF) and electron drain to the probe is demonstrated. To accomplish this one must use the portion of the current-voltage curve (CVC) in the region of the null of the third derivative of the probe current. Given a drain parameter < 1 for a wide class of EEDF and arbitrary value of . for a rapidly falling EEDF this permits determination of <> with an accuracy of 20%. For an EEDF close to equilibrium the maximum uncertainty of <> determination by this technique does not exceed 50%.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 44–49, May, 1988.