Kinematically complete investigation of momentum transfer for single ionization in fast proton-helium collisions

The dynamics of singly ionizing proton-helium collisions have been studied experimentally for several energies of the projectile (0.2, 0.5, 1.0 and 1. 3 MeV) with the technique of cold target recoil-ion momentum spectroscopy ( COLTRIMS). The complete final-state distribution in momentum space of all t hree particles was determined by measuring the three momentum components of the emitted electron and the coincident recoiling target ion. The momentum transfer and energy loss of the outgoing projectile was determined by mome ntum and energy conservation laws. Doubly differential cross sections of th e kinematically complete experimental investigation are presented. The pres ent data are compared with results from fast highly charged heavy-ion impac t experiments.