A study of the (α, t) reaction on 19F, 27Al, 51V and 59Co

The angular distributions of tritons from the (α, t) reaction on ¹⁹F, ²⁷Al, ⁵¹V and ⁵⁹Co nuclei corresponding to the (0⁺) ground states and (2⁺) excited states in the final nuclei have been measured in the angular range between 15° and 170° at α-particle energies of 25 MeV. For reactions on ²⁷Al and ⁵¹V nuclei, the differential excitation functions have also been obtained at different angles of outgoing tritons at E_α from 20 to 25 MeV. The experimental angular distributions are analysed by the DWBA approximation on the assumption of a nucleon stripping mechanism. The analyses of the present results and the data obtained earlier for the (α, t) reaction on the 1 p shell nuclei, A ? 30, reveal that the distinguishing feature of the reaction under study is the presence of backward angle peaks in the reaction cross section, which appear to be associated with exchange processes. For the (α, t) reaction on the heavier nuclei (A > 30), the dominant mechanism is nucleon stripping.