Projectile angular-differential cross sections for transfer and transfer-excitation in α–He collisions

Abstract

Total as well as projectile angular-differential cross sections for transfer and transfer-excitation have been investigated in collision of α-particles with helium atoms in the energy range 50–5,000 keV/amu. The four-body Coulomb–Born distorted wave formalism and boundary corrected continuum intermediate state approximation have been applied for this rearrangement collision. In both methods dynamic electron correlations have been taken through the complete perturbation potentials in post form. It is shown that for single electron-transfer, the ground state capture is dominant and the contribution from excited states to the total cross section is less important. It is also noted that the cross sections for transfer with target excitation channel have minor contribution to the total cross sections. We have also studied the total cross sections for single electron transfer from lithium atom by α-particle impact in the energy range from 50 to 3,000 keV/amu. Present computed results, both in prior and post forms of the transition amplitude for symmetric and asymmetric collisions, agree reasonably with the available theoretical and experimental results.