Approximate Theoretical Calculation of Continuum Opacities

摘要

An approxhnate procedure is described for the theoretical calculation of the spectral absorptionudcoefficient produced by bound-free and free-free transitions in plasmas containing polyelectronicudatoms and ions. Our method of calculation is based on the assumption that only two ionized species make important contributions to the opacity and that these two ionicudconstituents are present in equal concentrations. The approximate formulas are shown to yield results that are in good accord with estimates based on detailed numerical computations for nitrogen.