IMPROVED LOW-ENERGY DEPENDENCE OF CALCULATED CROSS-SECTIONS FOR THE K-SHELL IONIZATION OF ATOMS USING THE DEUTSCH-MARK FORMALISM

We present an improved formula to describe the energy dependence in th e low-energy regime of calculated atomic K-shell ionization cross sect ions using the semiclassical Deutsch-Mark formalism. The modified ener gy dependence was obtained from a fitting procedure using recent K-she ll ionization cross section data for atomic sulfur. A comparison of ca lculated K-shell ionization cross sections using this modified energy dependence with (1) critically evaluated experimental data for 11 othe r atoms and (2) cross section shapes derived from other predictive for mulae revealed good agreement, not only in the low-energy regime, but also at relativistic impact energies. (Int J Mass Spectrom 177 (1998) 47-50). (C) 1998 Elsevier Science B.V.