An electronic circuit for obtaining electron velocity distribution functions in plasmas

A new electronic method for obtaining electron velocity distribution function in glow discharge plasma is described. The method involves the use of operational amplifiers to obtain first and second time derivatives. The method has been tested to obtain such functions in plasma under the action of external axial magnetic fields. Agreement between plasma temperature values obtained using this method and those from direct current-voltage measurement is obtained. (authors). 11 refs., 3 figs. 2 tabs