Photoelectric cross section and mass attenuation coefficient for Cu, Co, Ni and CoCu, CoCuNi alloys using Fermi-Thomas model

Abstract

K-shell photoelectric effect cross sections were calculated for the elements Co, Cu and Ni, in the energy range from 10 keV to 30 keV. The method used was based on the use of nonrelativistic treatment for the electron in screening Coulomb potential. Fermi-Thomas model was used to represent the screening potential. Schrödinger equation could be solved accurately in spherical coordinates. The normalization of the continuum state wavefunction was obtained using Wentzel, Kramers and Brillowin (WKB) approximation. The results were given analytically and compared with the full relativistic screened calculations of Scofield. The mass attenuation coefficient was calculated for the CoCu, CoCuNi alloys and the results were compared with the experimental values reported by Seven. The results of this method were less accurate than those based on other methods like the self consistent field model for the atom. The value of this method lies in its simplicity and it can be presented analytically. The large difference between Seven and the theoretical ones was also investigated.