A PHENOMENOLOGICAL THEORY OF NEGATIVE GLOW OF ANOMALOUS GLOW DISCHARGES CONSIDERING VOLUME RECOMBINATION

Two-dimensional solutions of the quasi-neutral diffusion equation of a cylindrical negative glow plasma are computed numerically with regard to the radial contraction of the electron beam generating the plasma and to volume recombination terms linear or quadratic in the plasma density. Comparing calculated to measured maximal plasma densities (for H2-discharges) it can be shown that a linear recombination mechanism seems to prevail. Attachment coefficients calculated are about 2 to 5 · 105 (Torr sec)-1. An analytic description of the negative glow is given for the attachment case; it also allows to treat an additional gereration by electron-gas-collisions. Both the beam-contraction and attachment lead to a pressure-independence of calculated plasma efficiencies, as it was found experimentally. © 1969 Springer-Verlag.