L-shell ionisation of some heavy elements by proton and helium ion impact

Abstract The L-X-ray production cross sections for L α1, 2 , L γ 1, 5 and L γ2, 3, 6 transitions have been measured for thin targets of nine heavy elements (Ag, Sn, Sb, Te, Ho, Ta, W, Pt and Bi) by proton and helium ion impact in the energy range 1.5 to 3.8 MeV. The ionisation cross sections for the L 1 , L 2 and L 3 subshells were extracted using fluorescence and Coster- Kronig yields of Krause and emission rates of Scofield. The influence of the uncertainties of these atomic parameters on the resulting cross sections was taken into account and discussed. The measured L-subshell ionisation cross sections were compared with results reported by other authors and with predictions of the ECPSSR theory of Brandt and Lapicki. Possible explanations for the observed discrepancies for the L 1 −, L 2 − and L-subshells are discussed.