Double effects of projectile charge state on Nb L-shell ionization by slow highly ionized Xe ions

Nb L-shell ionization cross sections induced by Xeq+ (12 ≤ q ≤ 29) ions were measured as a function of the incident charge state q in the energy ranging from 1500 to 2500 keV. In this experiment, we observed a new dependence phenomenon that ionization cross sections revealed an increasing first and then decreasing trend with increasing q, which is different from the previously reported charge state-dependent behavior. New results are interpreted as evidence of charge state double effects on the inner-shell ionization in ion–solid collisions.