Multi-method treatment of elastic scattering of alpha particles from atomic hydrogen over a wide impact energy range

Abstract

Multiple theoretical methods are used to calculate the elastic scattering cross section for collisions of alpha particles with atomic hydrogen in the center-of-mass energy range of 10−4–108 eV. At the lowest energies where elastic scattering greatly dominates other reaction channels, a single-channel quasi-molecular-orbital approach is used. With the opening of inelastic channels at higher energies the multi-channel atomic-orbital, close-coupling method is applied, and at the highest energies considered perturbation theory (the Born approximation) is used. The results are compared with other data available in the literature and from preliminary multi-channel molecular-orbital, close-coupling calculations in order to assess the accuracy of the results and to create a recommended set of data spanning the entire energy range. The data is made available for use in astrophysical modeling and other plasma science applications online.