K-shell ionization cross sections of Cu, Zn and Ge by 3–5 MeV/u Si-ion bombardment

The K x-ray spectra of different targets (Cu, Zn, and Ge) induced by 3 to 5 MeV/u Si projectile ions have been measured to determine the K-shell ionization cross-section. A significant difference is observed between the measurements and theoretical estimates, where the theoretical ones are about 28–35% of the experimental results. Such difference is reduced to a good extent 51%–56% if multiple ionization effects are taken into account. Remaining discrepancy may be attributed to the electron capture contribution.