Semi-classical interpretation of the vector analyzing power in sub-coulomb neutron-transfer reactions

Sub-Coulomb neutron-transfer reactions are considered in a classical model in which the incident and outgoing projectiles follow Coulomb scattering trajectories with coincident turning points. The dependence of the vector analyzing power on bombarding energy and Q-value, and the angular dependence of the cross section are explained. The sign of the analyzing power is related directly to the total angular momentum transfer. Predictions of the model for (d, p) and (d, t) reactions are compared with DWBA calculations employing only Coulomb distortions. Limitations of the model are discussed.