We are studying the charge transfer in atom-surface scattering using a recently developed many-body theory. The final population of the atom is studied as a function of the surface workfunction, which has a strong effect on the final population. The effects caused by degeneracy, surface bandwidth and velocity are investigated. The formation of the Kondo peak, strongly controls both the initial population and the rate of charge transfer, and consequently the final population. The results show a strong degeneracy and velocity dependence for both the positive and negative ion. For the negative ion we also find a significant bandwidth dependence.