A simple two-component (beam + background) model for the frequency distribution of a resonance line excited by electron bombardment in an atomic-beam light source is described. The model is used to interpret the observed emission of the 1048- and 1067-Å resonance lines of argon. The model parameters provide information about the effective collimation of the beam, recoil broadening of the line shape, and the effects of background gas in the light source.
Steven C. Seitel and David K. Anderson, "Two-component model of an atomic-beam light source," J. Opt. Soc. Am. 64, 884-886 (1974)