Absorption and emission spectra of alkaline-earth atoms in liquid helium: a theoretical study

The absorption and emission spectra of Mg, Ca, Sr and Ba atoms in superfluid He are calculated systematically by using an adiabatic line-broadening theory modified by inclusion of the bubble-oscillation effect. The present study, which incorporates a more accurate description of molecular electronic states fora diatomic system than that used in an earlier model calculation, results in satisfactory agreement with experimental spectra.