Charge distribution of Ar recoil ions produced in one- and two-electron capture collisions by 16-MeV Oq+ projectiles.

Abstract

The yields of Ar recoil ions produced in collisions with 16-MeV ${\mathrm{O}}^{\mathrm{q}+}$ (q=3--8) were measured in coincidence with one- and two-electron capture by the projectile. Time-of-flight analysis identified the charges of the Ar recoil ions and enabled the determination of charge-state distributions. The independent-electron approximation was employed along with a simple exponential parametrization of the ionization and capture probabilities to calculate the cross sections for multiple ionization accompanied by one- and two-electron capture. By accounting for direct L-shell ionization and Auger multiplication of L-shell vacancies, good agreement between calculated and measured charge-state distributions was attained.