Distribution of exit silicon ions over excited states after penetrating through carbon foils at 2.65, 4.3 and 6.0Â MeV/u

Based upon the present method, it is found that the fractions of excited Si ions after the carbon foil are about 57%, 33% and 15% at energies of 2.65, 4.3 and 6.0 MeV/u, respectively, clearly indicating the significant reduction of the excited-ion component with the collision energy increasing. The calculated equilibrium charge-state fractions Fq∞ for Si ions are in good agreement with available experimental data.