Effects on partial frequency redistribution R(II) on the level population ratios in a resonance line

Abstract

Simultaneous solutions of the radiative transfer equation in the comoving frame and the statistical equilibrium equation, for a non-LTE two-level atom, have been obtained by means of angle-averaged partial frequency redistribution. The population density ratios of the upper and lower levels of the PV resonance line are also given, together with line source functions for different types of expanding gas density and velocity variations. The atmosphere presently considered is taken to be 11 times as thick as the stellar radius