Excitation-autoionization cross-sections and rate coefficients for Ge-like ions

Results of cross-section and rate coefficient calculations for electron impact direct and indirect ionization of ions belonging to the GeI isoelectronic sequence (ground 3d(10) 4s(2) 4p(2)) are presented. The cross-sections are given at near threshold energies for the five ions Kr4+, Mo10+, Xe22+, Pr27+ and Dy34+. The rate coefficients are computed for all the ions from Kr4+ to U60+ in the GeI sequence at seven electron temperatures (kT(e) = 0.1E(I), 0.3E(I), 0.5E(I), 0.7E(I), E-I, 2E(I) and 10E(I), where E-I is the first ionization energy). The calculations include the contribution of direct ionization (DI) calculated with the Lotz formula approximation and the contributions of excitation-autoionization ( EA) calculated in the framework of the distorted wave (DW) approximation for the 4s - nl, 3d - nl and 3p - nl resonant inner-shell excitations. The ionization enhancement due to the EA channels is shown as a function of Z along the GeI isoelectronic sequence.