Singly differential studies of one-electron processes in He2+−He collisions

The differential ^3He^2+-He scattering problem is investigated using the two-center wave-packet convergent close-coupling method in the incident energy range of 50--630 keV/u. The present two-electron approach accounts for electron exchange between reaction fragments and uses the configuration-interaction method to treat the target structure. We also apply a simpler method based on the effective one-electron target description. The singly differential cross sections are presented for electron capture, elastic scattering, excitation, and ionization of the target. The paper demonstrates the importance of the electron-electron correlation at lower projectile energies for the electron-capture and elastic-scattering processes. The two-electron results for electron capture into the ground state describe the available experimental data very well at all projectile energies, while the effective single-electron model shows good consistency at energies starting from 300 keV/u. For ionization, we observe a good level of agreement between the two approaches for all types of singly differential cross sections, and they agree well with the experimental data, wherever available. In addition, the angular differential cross sections for ground-state and total electron capture are presented for ^4He^2+-He collisions at the projectile energies of 62. 5, 125, 187. 5, and 250 keV/u. The angular differential elastic-scattering and excitation cross section and all three types of the singly differential ionization cross sections are found to be practically the same as the corresponding results for ^3He^2-He collisions.