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A determination of the angular distributions, β, and relative partial photoionization cross sections, σ, of the valence satellite lines of atomic scandium in the region of the 3p → nd, ms excitations has been carried out using electron spectrometry in conjunction with monochromatized synchrotron radiation. This work is complementary to our earlier study of the partial cross sections of the Sc valence satellites but now includes angular distribution measurements of the most intense satellite lines. A correct theoretical description of the experimental satellite σ and β values presented herein should help in rectifying present discrepancies between theory and experiment for the 3d and 4s mainline σ and β values.

The partial cross sections, σ, and the angular distribution parameters, β, of the photoelectrons originating from the 4f and 6s subshells of atomic thulium have been measured in the region of the 5p excitations (23 eV–38 eV). In qualitative agreement with a previous absorption study, our σ curves show two regions of strong resonance enhancement, one around a photon energy of 27 eV corresponding to 5p3/2 excitations and the other near 32 eV corresponding to 5p1/2 excitations. The β curves show considerable variation between the allowed extremes of −1.0 and 2.0 for many of the 4f photolines. In addition, the 6s photoline shows very marked deviations from β = 2.0 which is indicative of an open-shell atom. We also compare our experimental results with our calculated 4f partial cross sections. While there is excellent qualitative agreement between theory and experiment, quantitative details are not reproduced: (i) the 5p3/2 excitations are too narrow, (ii) while the 5p1/2 excitations have an intensity that is substantially less than what is observed experimentally.