The investigation of electron-ion radiative and dielectronic recombination in high-temperature plasmas. Progress report for 1989--1990

Abstract

(1) The unified description of radiative and dielectronic recombination has been extended to treat processes involving more than a single state of the initial ion, the autoionizing resonance, and the recombined ion. The major theoretical effort is now centered on the generalization of this description to self-consistently incorporate the effects of charged-particle collisions and plasma electric fields. (2) The K{sub {alpha}} model for the dielectronic satellite spectra of highly-charged Fe ions has been incorporated into the multi-ion-species transport code developed at the Princeton Plasma Physics Laboratory. The immediate objective is to produce a realistic simulation of the observed Fe K{sub {alpha}} spectra from PLT and TFTR. (3) A detailed investigation is in progress involving calculations of the dielectronic recombination satellite spectra in the presence of a distribution of plasma electric microfields. The calculations have been carried out for the lowest-lying n=2 satellites, which are affected by the electric fields only in high-density laser-produced plasmas. (4) The investigation has been completed on the effects of indirect processes involving autoionization resonances for electron-density sensitive line-intensity ratios. The resonance contributions have been found to be comparable with the direct electron-impact excitation rates for magnetic-quadrupole transitions in high-charged ions. Line intensity ratios have been identified which are sensitive to density in the density region of characteristic tokamak plasmas.