Effect of Continuum Electrons on Superconfiguration Electronic Structure

Accurate calculations of opacities of plasmas often require explicit account- ing of a large number of atomic configurations in order to obtain reasonable agreement with experimental spectra. The problem of accounting for the most influential configurations can become especially difficult for plasmas at so-called warm dense matter conditions, when the charge state distribution of ions is spread over many ion stages and therefore the number of relevant atomic con- figurations can easily exceed one billion. The superconfiguration concept was developed to treat this problem by formally averaging over all possible configura- tions in order to obtain a representative atomic structure [1,2]. We present a new implementation of the superconfiguration approach which self-consistently in- cludes the influence of continuum electrons when determining the atomic struc- ture, and we analyze the impact of such an approach on spectral calculations in plasmas with significant populations of low-energy continuum electrons.

[1] A. Bar-Shalom, J. Oreg, W. H. Goldstein, D. Shvarts, and A. Zigler, Phys. Rev. A 40, 3183, 1989; [2] T. Blenski, A. Grimaldi, F. Perrot, JQSRT 65, 91-100, 2000