Multiple ionization in fast ion-atom collisions: simultaneous measurement of recoil momentum and projectile energy loss

We report on the first experiment that measures simultaneously the full momentum vector of recoil ions and projectile energy loss and scattering angle in ion-atom collisions. We studied multiple ionization in the collisions of 0.83-MeV/u O7+ with Ne. Recoil ions ( Ne(q+), q = 1-8) were detected in coincidence with single capture to O6+. The results give the first experimental evidence for the increase of the average electron energy with increasing recoil charge state q. The average ejection angle shows a dramatic decrease with q. Results are compared with n-electron classical trajectory Monte Carlo calculations.