Study of the L-shell x rays of Ta, Pt, Au, Hg, and Pb by proton bombardment

The L x-ray transition ratios L (α12/l), L (γ1/eta), L (eta/γ5), L (γ236/γ1), and L (γ44/sub prime//γ1) have been measured for the elements 73Ta, 78Pt, 79Au, 80Hg, and 82Pb by ionization of the L-subshell electrons with 0.4--2.0-MeV proton bombardment. Transition-rate ratios L (γ23/γ44/sub prime/) to the L1 subshell, L (γ6/γ1), L (γ1/eta), and L (eta/γ5) to the L2 subshell, and L (α12/l) to the L3 subshell have been extracted. Comparison of the extracted ratios with the relativistic Hartree-Fock model calculations of Scofield shows agreement within experimental errors for the L1, L2, and L3 subshell ratios. A previously reported minimum in the Pb L (α12/l) ratio between proton energies 1.0 to 1.5 MeV was not observed. Total L-shell production cross sections have also been measured for Pt and Au over the energy range 0.4--2.0 MeV and are found to be in good agreeement with the predictions of the nonrelativistic plane-wave Born approximation and the constrained binary-encounter approximation, but not with the binary-encounter approximation