Radiative opacities of hot and solid-dense aluminium plasmas using a detailed level accounting model

Abstract

An approach based on the self-consistent-field (SCF) multi-configuration Dirac–Fock (MCDF) model is developed to simulate radiative opacity of hot and solid-dense plasmas taking detailed levels into account. The correlation effects and the angular momentum coupling among the bound electrons are treated in the usual way employed in a normal MCDF method. Influences of plasma screening on transition energies, oscillator strengths and ionization potentials are included by introducing a correction to the one-electron potential to account for the screening of the ionized electrons. This correction depends on the detailed micro-space distribution of the ionized electrons in different ions. The total average number density of the ionized electrons in the plasma is obtained by solving the Saha equation with quantum degeneracy corrections. The ionized electron density distribution in each ion is described based on a Thomas–Fermi distribution in an atomic field. Since the electronic structure and the ionization balance depend on each other, the SCF procedure includes solving the MCDF and the Saha equations. As examples, calculations have been carried out to simulate the spectrally resolved radiative opacity and the Rosseland and Planck means of hot and solid-dense aluminium plasmas. Comparisons between the results of the present model, average atom model and experiments are made to show the significance of detailed line-by-line treatments on the calculated results.