Dense plasma effects onK-shell dielectronic satellite lines

The dielectronic satellite lines from the $n=2\mathrm{}$ doubly excited levels of lithiumlike and heliumlike ions have been studied theoretically in dense-plasma environments. A comprehensive level structure including ground, singly excited, and doubly excited levels was included in a collisional-radiative equilibrium model to calculate level populations and the satellite intensities self-consistently for carbon, aluminum, and argon plasmas. The effects of inner-shell excitation rates (calculated via the distorted-wave approximation with configuration mixing) and collisional ionization and recombination of the doubly excited levels are included in the model and their effects on the satellite intensities assessed. The well-known heliumlike intercombination-to-resonance line ratio, used in density determinations, is shown to be strongly affected by blended satellite lines at high density, causing significant error in the measured density when their intensities are not accounted for.