Auger rates on NaCl(0 0 1), effect of the final state and modeling via an effective length

Neutralization of keV He+, Ne+ and F+ ions colliding on NaCl(0 0 1) at grazing incidence is studied by energy loss in coincidence with emitted electrons. Three closely related Auger-like mechanisms are identified. In all processes, two electrons are removed from the valence band, one is captured on the ground state of the neutral projectile whereas the remaining electron is found either in the electron continuum, in the conduction band or in a surface excited state. To help comparing the three different processes, a procedure is proposed that allows a first order correction of so-called trajectory effects on the observed neutralization fraction without a priori knowledge of the detailed trajectory.