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DOE OSTI · 22852457

Dirac–Fock photoionization parameters for HAXPES applications, Part II: Inner atomic shells

Abstract

Highlights: • Photoionization parameters are given for inner atomic shells with binding energies ≳ 1.5 keV. • The data are extension of our calculations for use in the HAXPES spectroscopy studies. • Relativistic calculations were performed by the Dirac–Fock method. • Photoionization cross sections were calculated including all multipoles. • The angular distribution parameters were obtained in the quadrupole approximation. - Abstract: Presented here are the photoionization cross sections and parameters of the photoelectron angular distribution for inner atomic subshells with binding energies beyond 1.5 keV in the photon energy range from 2 keV to 12 keV. The calculations are an extension of our previous paper containing the photoionization parameters for comparatively outer shells with binding energies lower than 1.5 keV (Trzhaskovskaya and Yarzhemsky, 2018). The calculations are intended for use in the experimental HAXPES spectroscopy investigations. The up-to-date HAXPES activity tends to increase the photon energy to investigate the deep core levels resulting in a necessity of theoretical consideration of photoionization parameters for inner atomic shells. Our relativistic calculations have been performed by the Dirac–Fock method. The photoionization cross sections have been found including all multipoles of the radiative field while the photoelectron angular distribution parameters have been obtained in the quadrupole approximation. The effect of the hole resulting in the atomic subshell after photoionization has been taken into account using the frozen orbital model.

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BibTeXRIS

2019-09-15. Dirac–Fock photoionization parameters for HAXPES applications, Part II: Inner atomic shells. https://doi.org/10.1016/j.adt.2019.05.001

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