Asymptotic solutions for a symmetric plasma under ionization nonequilibrium

Leading-order solutions for electron and ion density, electron and ion velo city, and electric potential have been obtained in a planar, symmetric geom etry for the case of a dense, low-temperature plasma bounded by perfectly a bsorbing walls. The solutions are obtained in terms of the Jacobi elliptic functions. These solutions are shown to reduce to those previously obtained for the case of a semi-infinite plasma when the appropriate transformation s are applied. The solutions are also shown to reduce to the well-known sol utions from linear diffusion theory, in terms of circular functions, when t he linear source approximation is made. The solutions are evaluated and dis cussed for a representative thermal plasma where the influence of explicitl y accounting for recombination is illustrated. (C) 1999 American Institute of Physics. [S0021-8979(99)03721-4].