Energy spectra of ions and the energy dependence of the degree of ionization of atoms emitted from metals in a nonlinear sputtering mode

Analytical formulas have been obtained for the energy spectrum $F^+(E)$ of atomic ions and the energy dependence of the degree of ionization $\alpha^+(E)$ of atoms sputtered from metals in the nonlinear collision cascade mode. The comparison of the dependences $\alpha^+(E)$ for the linear and nonlinear sputtering modes indicates a significant difference between the mechanisms responsible for the formation of the charge composition of atomic ions.