Resonance-Line Transfer with Partial Redistribution: a Preliminary Study of Lyman a in the Solar Chromosphere

This paper presents a method for solving resonance-line transfer problems including a detailed treatment of the effects of partial redistribution. Calculations were madefor a schematic representation of La in the solar chromosphere. We find that the usual assumption bf complete redistribution leads to spurious estimates of number densities, the Lyman continuum, and the La profile, and thus we support the conclusions of Vernazza and of Vernazza, Avrett, and Loeser. Although we have made too many simplifications in the current computations to be able to compare with the observed La profile in detail, the differential behavior of our results for several cases supports the suggestion made in the papers cited above that the scattering in the La wing is well described as dominantly coherent. The methods developed here are easily extended to more realistic models and can be applied to many other lines of interest. Subject headings: chromosphere, solar - line formation - radiative transfer