Charge exchange of low energy particles passing through thin carbon foils: Dependence on foil thickness and charge state yields of Mg, Ca, Ti, Cr and Ni

Abstract

We experimentally investigate charge exchange of ions passing through thin carbon foils of 1.1–10 μg/cm 2 thickness at incident energies from 0.5 to 5 keV/u. At such low energies usually only the charge exchange processes occurring at the back surface determine the final charge state of the emerging projectiles. However, for some elements we observe a significant foil thickness dependence which cannot be explained by current theoretical models. Possible reasons for this thickness dependence are discussed in this paper. We further present new data on charge state yields for Mg, Ca, Ti, Cr and Ni.