Asymptotic Expansions of the Integrated Absorptance for Simple Spectral Lines and Lines with Hyperfine Structure and Isotope Shifts

Asymptotic expansions of the integrated absorptance for weak and strong lines are given for both simple spectral lines and lines with hyperfine structure and isotope shifts. We have taken into account the separation and relative intensities of the different lines as determined by quantum mechanics. The lines are assumed to have a Voigt profile.