Multiphoton excitation of autoionizing states of Mg: Line-shape studies of the 3p2S1state

Abstract
We have observed ionization of Mg by both direct and stepwise two-photon excitation of the 3p2 1S state. The line shape of the single-color direct process is strongly modified by the resonance denominator associated with the intermediate virtual state. The measured energy and width of this resonance as determined by the stepwise two-color technique agree well with previous determinations.