Dependence of the angular distribution of atomic photoelectrons on energy and Z

Abstract

The angular distribution of photoelectrons from atomic p-subshells has been investigated within the framework of the Hartree—Slater central field model for the atom. Calculations have been performed for 2p, 3p, 4p, 5p, and 6p subshells for a wide range of elements over the entire periodic system for energies from threshold to 18 rydbergs (∼ 250 eV) above threshold in each case in an effort to understand the combined energy and Z-dependence of the asymmetry parameter β. It was found that in all cases there is a rapid variation in β with energy near threshold due to changes in the coulomb phase shifts. Further, the overall shape of the β versus energy curve for a given subshell is very different depending upon whether the cross section for that subshell has a Cooper minimum or not. The reasons for this behavior are discussed and the results are compared with available experiment which showed generally good agreement. Finally the applicability and accuracy of these results is discussed along with a prospectus for further work.