Experimental study of atomic 4<i>d</i>giant resonances by photoabsorption and photoelectron spectroscopy: Ba, La, and Ce

Abstract

Total and partial (4${\mathit{d}}^{\mathrm{\ensuremath{-}}1}$,4${\mathit{f}}^{\mathrm{\ensuremath{-}}1}$,5${\mathit{s}}^{\mathrm{\ensuremath{-}}1}$5${\mathit{p}}^{\mathrm{\ensuremath{-}}1}$,5${\mathit{d}}^{\mathrm{\ensuremath{-}}1}$6${\mathit{s}}^{\mathrm{\ensuremath{-}}1}$) sections of atomic Ba, La, and Ce have been determined by absorption and photoelectron spectroscopy in the range of the giant 4d\ensuremath{\rightarrow}(4f,\ensuremath{\epsilon}f) resonances. Many electron theories that take polarization and relaxation effects into account describe the gross features of the spectra but in many cases fail to reproduce the exact energy positions, line shapes, and amplitudes of the resonances in the cross sections of the main and satellite lines.