Electron-ion recombination and plasma field effects

Abstract

A systematic approach to the plasma field effects on atomic processes is presented, in which the many‐body, stochastic nature of the plasma electron and ion perturbations is taken into account by appropriate plasma averaging procedures. It involves three self‐consistent steps: (A) Effective plasma potentials are derived using proper plasma averaging. (B) The atomic transition amplitudes are evaluated using the distorted states. (C) Finally, the distorted rates are inserted into the rate equations for determination of population densities of excited states and effective rates. As preliminary to more extensive calculations, the theory is applied to hydrogen plasma. The collisional radiative model is analyzed to show the salient features of the effects of plasma perturbations on the electron‐ion collisional radiative recombination and ionization rates. The effect of nonequilibrium plasmas is studied using a simple two‐temperature model; the collisional ionization rates are very sensitive to the mixed component. The Rydberg states distorted by the plasma field is treated by a continuous Fokker‐Planck approach.