The finite temperature random phase approximation as a coupled-channel problem and the implementation of the single-channel random phase approximation (SCRPA) for the He atom in a finite temperature dense plasma

Abstract

A theoretical approach for the description of “excited states” of an atom/ion in hot and dense plasmas is presented. It is based on the random phase approximation (RPA) for finite temperature fermion systems discussed earlier. It is shown here that after angular momentum and spin analysis are performed, the fundamental equations of the finite temperature RPA equations obtain the form of a coupled channel, coupled component integro-differential equation system, just as in the T=0 temperature case. Subsequently, the single-channel, uncoupled component approximation is introduced. A computer code written for this approximation was tested and results for He plasma at kT=10 eV and densities ranging from 10 18 to 10 23 atoms/cc are presented and discussed.