Electron capture and target excitation in intermediate-energy He+-H collisions

We present all-electron close-coupling calculations of cross sections for electron capture and target excitation occurring in 0.25-200 keV/u He+-H collisions. We show overall good agreements with available experimental data for total electron capture, n = 2 target excitation, and related H a emission. We especially focus on n l-selective capture and excitation processes and critically compare our results with those from previous theoretical investigations. Our results confirm the oscillatory structures observed in the spin-averaged H(2s) and H(2p) excitation cross sections for impact energies below 50 keV/u. Furthermore, we interpret these oscillations as the consequence of interferences between excitation to H(2s) and H(2p(0)) in both spin-singlet and spin-triplet symmetries, as well as between electron capture to He(1s2p P-1, |M-L| = 1) and excitation to H(2p(1)) in spin-singlet symmetry.