Semiempirical Flare Models with Chromospheric Condensation

Abstract

Using Hα line profiles observed for two flares, we have constructed series of semiempirical models with chromospheric condensation. From the semiempirical point of view, it is shown for the first time that chromospheric condensations are responsible for the Hα line asymmetries, not only for the red-asymmetry, but also for the blue-asymmetry with a central reversal. The properties of the condensation and its calculated evolutionary tendency seem to be consistent with the results of current hydrodynamical models of solar flares. The results also show that for the first flare, the Hα can be explained merely by introducing the condensation without any need to heat the chromosphere, while for the second flare, the condensation has to overlap a heated chromosphere.