NEW PARAMETERS FOR THE CALCULATION OF L-SUBSHELL IONIZATION CROSS-SECTIONS

New parameters for the calculation of L subshell ionization cross sect ions using a semiempirical expression are presented. The parameters we re obtained by fitting an analytical function to the experimentally ob tained values of L subshell ionization cross sections. The experimenta l data included compilation of the published data from 1975 to 1982 by Sokhi and Crumpton as well as our newly compiled data published in 19 82-1991. The number of data employed for the fitting was 2295, 3 1/2 t imes more than that used in Miyagawa's work. The data were divided int o six groups according to the Z values: 14 less-than-or-equal-to Z les s-than-or-equal-to 42, 43 less-than-or-equal-to Z less-than-or-equal-t o 50, 51 less-than-or-equal-to Z less-than-or-equal-to 60, 61 less-tha n-or-equal-to Z less-than-or-equal-to 70. 71 less-than-or-equal-to Z l ess-than-or-equal-to 80 and 81 less-than-or-equal-to Z < 92. Each was fitted by the analytical function to obtain the parameters for the cal culation of L1, L2 and L3 subshell ionization cross sections. For data in the group with Z less-than-or-equal-to 42. only parameters for the calculation of L total ionization cross sections were determined. A c omparison of the various theoretical predictions with the experimental data and the fits is also presented.