High order asymptotic expansions of the four kernel functions for line formation with the Voigt profile

Abstract

Analytical expressions are given for the coefficients, as a function of the Voigt parameter a, in the asymptotic expansions of the kernel functions K 1( π), K 2( π), M 1( π), and M 2( π) that describe the transfer of radiation scattered with complete redistribution over a Voigt profile.