Dielectronic satellite spectra for highly-charged helium-like ions - VII. Calcium spectra - theory and comparison with SMM observations

Abstract

The atomic theory, developed in earlier papers in this series for iron, has been applied to the spectra from calcium. This includes the production of satellite lines by dielectronic recombination and inner-shell excitation, as well as the production of helium-like spectra by excitation, radiative and dielectronic recombination and through cascades. Two methods are described for fitting observed spectra, to determine the plasma physical parameters. The results are applied to the observations from the soft X-ray Polychromator of the flare on 1980 May 21. The good agreement between computed and observed spectra gives support to the accuracy of the theory presented. Analysis of the time variations shows that the flare is close to steady-state ionization balance throughout.