The 5p absorption spectrum of laser-excited barium

The 5p absorption spectrum of laser-excited atomic barium has been investigated in order to probe the changes in correlation between the 6s and 5d subshells. A pulsed tunable dye laser was used to populate the 6s5d states via the resonantly excited 6s6p 1 P 1 level. The 5p absorption spectrum between 50 and 85 nm was recorded at two different delay times, using as a pulsed continuum source a laser-generated plasma, formed by focusing a ruby laser onto a samarium target. The excited spectra show a very large number of new absorption features, most of them sharp but a few of them broad and quasimolecular in appearance.