Excitation of Hydrogen and Ca II Under Chromospheric Conditions

Abstract

Methods are described for calculating excitation conditions in a hot gas in the absence of local thermodynamic equilibrium, taking self-absorption into account, in the approximation that excitation is uniform throughout the medium. The equilibrium excited-state populations and the emission, attenuation, and scattering properties derived from them are tabulated for a variety of physical conditions appropriate to the -solar chromosphere (7500 < T < 50000oK; 1010 < N e < 1012 cm-3) for some of the main spectral lines of hydrogen and CalI.