A Coherent Derivation of an Average Ion Model Including the Evolution of Correlations Between Different Shells

Abstract

We propose in this short note a method enabling to write in a systematic way a set of refined equations for average ion models in which correlations between populations are taken into account, starting from a microscopic model for the evolution of the electronic configuration probabilities. Numerical simulations illustrating the improvements with respect to standard average ion models are presented at the end of the paper.

Exact Solution of a Fully General Non-Local-Thermodynamic-Equilibrium Two-Level Atom

“…2 ). This model is derived from the microscopic detailed description of the plasma by using a systematic procedure of moment closure [6]. More details about the distribution of states (such as the N (N + 1)/2 correlations between level populations [24]) can be obtained in a second step [15].…”