Ionization of K-shell electrons by highly relativistic protons

A comparative study of three theoretical formalisms by Anholt et al. (1976), Scofield (1978), and Becker et al. (1985) for K-shell ionization by highly relativistic protons has been carried out. The importance of the spin-flip mechanism is emphasized. It is concluded that in the analysis of such inner-shell ionization processes, an accurate description of the projectile-target interaction is of much more significance than the accuracy of the wave functions of the atomic electrons.