BINARY PEAK ENHANCEMENT AND STRUCTURE IN PARTIALLY STRIPPED ION ATOM COLLISIONS

Recent experiments have found both an unexpected enhancement and structure of the binary peak in the spectrum of electrons ejected in partially stripped ion-atom collisions. Utilizing the theoretical approach which has been used to elucidate the origin of this behaviour, a survey of their manifestation is presented over a broad range of nuclear and ionic charges (C, F, Fe, I and U ions) and impact energies (0.1 to 100 MeV u-1). For forward binary electron emission it is shown that the greatest enhancement occurs for the lowest projectile ion charge states (highly screened nuclei). The magnitude of the enhancement maximizes near an energy that is characteristic of each nuclear species and results in a cross section several times larger than that for impact by the fully stripped ion. Those ions, collision energies and ejection angles for which unusual binary peak structures are likely to be observable are illustrated. We point out what consequences these effects have for modelling energy deposition in the collision of ions with dense targets.