The role of prompt electrons in the post-collision effect in fast ion - atom collisions

Abstract

The influence of the post-collision Coulomb effect of direct-electrons on the Auger-line energy shift has been studied in fast proton - atom collisions. KLL and LMM Auger spectra of neon and krypton target have been measured and analysed with high precision. The semiclassical theory of the post-collision interaction (PCI) has been extended to include the effect of both the receeding projectile ion and the ejected prompt electron. Experimental and theoretical line-energy shifts exhibit a reasonable agreement in the entire angular range of the Auger emission. In a narrow cone around , the line-energy shift is influenced mainly by the PCI with the projectile ion, while at backward angles, it is predominantly governed by the ejected electron - Auger - electron interaction.