The influence of the continuum lowering on transition probabilites: competition between cancellation and opacity effects

Abstract

To take into account the influence of the continuum lowering (CL) on the spectra of the diverse ionic states in a plasma, we combine the Average Atom Model (AAM) with the Saha equations as well as a self consistent approach. The parameters of the AAM are introduced in a coupled system of Saha equations to find the densities and abundances of the different ions present at the given electron density and temperature. The eigenvalues εnl allow the calculation of the respective effective charges Znl, and these, in turn, the corresponding mean radius ⟨rnl⟩. The values of the continuum lowering arise from the ansatz ⟨rnl⟩ ≤ Ri/2, with Ri being the ionic radius. Variation of the net charge modify the wavefunctions and hence different observables (e. g., the transition probabilities). The variation of the transition probabilities Aif in terms of matter density N0 and the possible disappearance of some spectral lines is analyzed.