L-shell ionisation in very asymmetric ion-atom collisions

Abstract

We derive expressions for the path factors for arbitrary multipole transitions for a Rutherford trajectory in the semiclassical approximation for atomic ionisation. The usefulness of the method is illustrated by calculating L-subshell ionisation for light-ion impact on heavy atoms, including electronic relativistic effects and a realistic atomic target potential.

Kα1X-ray satellites of tantalum bombarded with fast nitrogen ions

“…For high collision velocities which exceed the electronic orbiting velocity in the initial state, an effective potential should be used for the construction of Gi and Gf in order to account for the presence of the passive target electrons. In our calculations we have used a variationally determined optimised potential (Aashamar et a1 1978, Aashamar and Amundsen 1988), which especially for the M shell noticeably changes the impact parameter dependence of PA as compared with the results for a screened Coulomb field.…”

A semiclassical theoretical model for (e-2e) processes

“…In these papers a linear trajectory was assumed and either hydrogen-like targets were considered or approximate hydrogenic wavefunctions were taken for the target electrons. Subsequently, this model has been considerably improved : Amundsen (1977) took account of the Coulomb deflection of the colliding particle through the use of a Rutherford trajectory and Aashamar and Amundsen (1981) investigated wavefunction effects. In recent work, Aashamar and Amundsen (1988) give analytic formulae for the path factors in the Rutherford trajectory case and Hansen and Kocbach (1989) have applied a simplified form of the SCA model to the calculation of triple differential cross sections for K-shell ionisation.…”