Cross sections have been determined for electron transfer, direct excitation, and ionization in collisions between $\alpha$ particles and $\text{H}\left(1s\right)$ atoms at $\alpha$ energies 3 keV–38.4 MeV, extending earlier work [Phys. Rev. A 25, 697 (1982)] restricted to total transfer at 20–200 keV. Transfer as well as excitation cross sections into individual states up to $3d$ have been determined with several coupled-Sturmian pseudostate bases, and tests of basis sensitivity have been carried out. These and ionization cross sections have been compared with existing experimental and other coupled-state results. Structure is observed in the lower-energy excitation cross sections, which is believed not to be an artifact of the bases used. Ionization and excitation cross sections have also been compared with corresponding Born results at higher energies.

• Received 7 September 2007

DOI:https://doi.org/10.1103/PhysRevA.76.062702