X-ray production cross sections, intensity ratios, and centroid energy shifts ofAg KandLandAu Lx rays produced byO16beams of 12-50 MeV

Abstract
The 12-50-MeV O16 beam-induced K and L x rays of Ag and the L x rays of Au from thin targets were studied with a Si(Li) detector. Absolute K and L x-ray production cross sections were derived from measured x-ray yields and compared to available theoretical calculations for inner-shell Coulomb ionization cross sections. Inclusion of Coulomb repulsion, binding, and (Z1Z2)3 effects in the plane-wave Born-approximation calculations gives good agreement with experimental values of σKX for Ag. The agreement between theory and experiment for L-shell ionization is not as good, possibly owing to the effects of multiple ionization on the fluorescence yield, although the energy dependence of σLX for Au is well reproduced. The energies of the Ag K α and K β and Au L α, L β, and L γ lines were observed to change with beam energy as did the intensity ratios of these lines. HFS calculations for the Ag K α and K β lines indicate that the observed shifts are probably associated with multiple M-, not L-, shell ionization.