Imaging of continuum states of theHe22+quasimolecule

Abstract

Using cold target recoil ion momentum spectroscopy (COLTRIMS) we have investigated the production of one free electron in slow ${\mathrm{He}}^{2+}+\mathrm{He}(1{s}^{2})$ collisions. At projectile velocities between 0.6 and $1.06\phantom{\rule{0.3em}{0ex}}\text{a.u.}$ (9--$28\phantom{\rule{0.3em}{0ex}}\mathrm{keV}∕u$), the fully differential cross section was measured state selective with respect to the second electron, which is bound either at the target or the projectile. We provide a comprehensive data set comprising state selective total cross section, scattering angle dependent single differential cross sections, and fully differential cross section. We show that the momentum distribution of the electron in the continuum image the relevant molecular orbitals for the reaction channel under consideration. By choosing the bound electron final state at the target or projectile and the impact parameter we can select these orbitals and manipulate their relative phase.