EXPERIMENTAL AND THEORETICAL-STUDY OF THE INHOMOGENEOUS ELECTRON KINETICS IN THE DC COLUMN PLASMA

The radial change of the electron velocity distribution function and o f related macroscopic quantities of the electrons are studied theoreti cally and experimentally in the positive column plasma of a neon de lo w pressure glow discharge. The theoretical investigations are based on the solution of electron kinetic equations. The measurements of elect ron kinetic quantities are performed by using a single probe technique with automated recording. To avoid the strict treatment of the compli cated radially varying electron kinetics in the microphysical descript ion of the column plasma, various simplifications of the appropriate i nhomogeneous kinetic equation have been adopted in,the past. Recently a strict solution approach of this complex kinetic problem could be de veloped. Using this strict solution approach and experimentally determ ined electron kinetic quantities the approximation quality, obtained b y applying various simplified approaches to treat the electron kinetic s as the conventional homogeneous approach, the nonlocal approach and the local field approximation, is illustrated and critically evaluated in this paper.