Charge State Studeis at the University of Notre Dame

Equilibrium charge state distributions have been measured for 3 -- 7 MeV lithium, boron, and carbon ions passing through carbon foils. The data are compared to the predictions of several semi-empirical models of charge equilibrium in the $\le $ 1MeV/u regime. The current work underscores the general problem of extrapolating models developed for high-Z projectiles to ions of low-Z. A compilation of experimental data for low-Z ions in the low energy regime has been used to re-parameterize a few of the charge equilibrium models for carbon foils. Experimental techniques, comments and suggestions on the nature of the equilibrium charge states of low-Z ions are presented.