Measurements of X-ray production cross sections at photon energies across the Li (i = 1–3) sub-shell absorption edges of 74W and 76Os using synchrotron radiation

Abstract

The cross sections for production of the Lk (k=l, η, α, β1,3,4,6, β2,15,5,7, γ1,5, γ2,3) X-rays have been measured at different incident photon energies ranging 10.2–13.1keV across the Li (i=1–3) sub-shell absorption edge energies of 74W and 76Os. These measured XRP cross sections, σLk(exp), exhibited significant differences with two sets of the theoretical values calculated using the Dirac–Fock (DF) model based X-ray emission rates provided by Campbell and Wang (1989), Dirac–Hartree–Slater (DHS) model based fluorescence (ωi) and Coster–Kronig (fij) yields given by Puri et al. (1993) and two sets of the Li (i=1–3) sub-shell photoionization cross sections based on the non-relativistic Hartree–Fock–Slater (HFS) model tabulated by Scofield (1973) and those deduced from the self-consistent Dirac–Hartree–Fock (DHF) model based theoretical total photoionization attenuation coefficients tabulated by Chantler (1995). However, the branching ratios (ILk/ILα)exp (k=l, β2,15) and(ILk/ILβ1)exp (k=γ1,5, η) are found to agree with the theoretical values.