Inner shell 4 Ionization 4 Multiple ionization 4 inner-shell Argon 2 CDW-EIS 2 Collisional ionization 2 Continuum distorted wave-eikonal initial state 2 Distortion (waves) 2 Ejected electrons 2 Helium 2 Independent particle models 2 Inner-shell electrons 2 Intermediate energies 2 Ionization probabilities 2 Kr 2 Krypton 2 Protons 2 Shells (structures) 2 Target electrons 2 Total ionization cross sections 2 Xe 2 Xenon 2 ionization 2 multiple 2 multiple ionization 2 post-collisional 2