THE EFFECT OF NONEQUILIBRIUM IONIZATION ON THE H-I LYMAN-ALPHA LINE ORIGINATING IN THE SOLAR-WIND SOURCE REGIONS

We investigated the effects of the deviations from ionization equilibr ium occurring in the plasma outflowing from the solar wind source regi ons on the intensity and profile of the H I Lyman-alpha line. In parti cular, we computed the densities of the ions of Hydrogen along a coron al hole model, with and without the assumption of ionization equilibri um. Analogously, we computed the ion densities in the unstructured qui et corona surrounding the coronal hole. These density values were used to calculate the intensity and profile of the Lyman-alpha line expect ed from the coronal structures considered, both in equilibrium and non -equilibrium conditions. The comparison between non-equilibrium and eq uilibrium results shows only some differences at heliocentric distance s higher than 5 R.. The importance of these results for the analysis o f the Lyman-alpha emission from the solar wind source regions has been discussed.