Incoherent scattering cross-sections due to L-shell electrons

The differential cross-sections (dsigmasub(L)) for the incoherent scattering of 662 keV gamma photons by the L-shell electrons of thorium, have been measured by the coincidence technique. These cross-sections are compared with the Klein-Nishina values dsigmasub(F) for free and stationary electrons and with those computed for all the atomic electrons of thorium on the basis of Thomas-Fermi and Hartree-Fock models. The deviations are explained. (author)