Electron capture by a -particles in hydrogen

A non-resonance charge-transfer reaction for x -particles in hydrogen is investigated by the use of an expansion based on atomic eigenfunctions as in Bates (1958), full account being taken both of the non-orthogonality of the eigenfunctions of the initial and final atomic states and of the effect of distortion. Cross-section for the reaction have been computed for a range of incident particle energies from 50 to 1600 keV. The results indicate that the effect of distortion is considerable up to energies of 800 keV. Comparison is made with the results obtained w hen the effect of the non-orthogonality is ignored (with and without the inclusion of the nuclear-nuclear term in the interaction potential).