The variation of photoelectron angular distributions with energy

Photoelectron angular distributions for the ionization of the outerp-shell of the rare gases Ar, Kr, and Xe, and of the outerS- andd shell of Hg, are measured at various photon energies obtained from rare gas resonance radiation. The distributions are found to agree with the theoretically predicted form. Values of the anisotropy parameter β are determined, and their dependence on electron energy is compared with available numerical results, as well as with model calculations performed in this work. In the case of Hg the possible influence of spin-orbit coupling on the β-values is discussed.