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Total photoion yield spectra in the vicinity of the 3d thresholds of Xe, Cs and Ba are presented. These spectra were recorded with higher photon energy resolution than previously reported. For xenon the new experimental data reveal additional structures. Employing Hartree-Fock calculations, the origin of the prominent resonances is explained: for Xe and Cs the main absorption features are caused by shape resonances above threshold, whereas for Ba it is revealed that the 4f orbital has finally collapsed and the sharp resonances are caused by discrete excitations into bound states.

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The photoion Li 2ϩ /Li ϩ production cross section ratio of ground-state atomic lithium has been measured for photon energies ranging from 80 to 424 eV. The absolute cross sections for the Li 2ϩ and Li ϩ yield are also derived. In this energy region, the Li 2ϩ /Li ϩ ratio reaches a plateau of about 1.0% before reaching a maximum of about 4.5%, then decreases slowly. Good agreement is found between the measured total photoionization cross sections of lithium and theoretical calculations. The Li 2ϩ /Li ϩ ratio is also compared to the He 2ϩ /He ϩ ratio from excited He(1s2s) for photon energies up to 70 eV above threshold. The branching ratio of Li 2ϩ to total Li ion production is also compared to the single-ionization cross section of electron impact on Li ϩ ions.