MEASUREMENTS OF RECOIL AND PROJECTILE MOMENTUM DISTRIBUTIONS FOR 19-MEV F9++NE COLLISIONS

The collision system of 19-MeV F9+ on Ne has been studied using recoil and projectile momentum spectroscopy. For each event, identified by f inal recoil and projectile charge state, the three-dimensional momentu m vector of the recoil ion and the transverse momentum vector of the p rojectile ion were measured. The transverse momenta of the recoil and projectile ions were found to be equal in magnitude and opposite in di rection, indicating that the transverse momentum exchange is dominated by interactions between the two ion cores. The transverse momentum di stributions are well described by nCTMC calculations. The longitudinal momentum distributions of the recoil ions show that a large fraction of the momentum transferred to the projectile is carried off by contin uum electrons. The recoil ions are scattered slightly backward, in par tial agreement with predictions of nCTMC calculations.