Single-nucleon transfer to unbound states in the 4He(α,t)5li reaction at incident energies of 120, 160, and 200 MeV
The 4He(α,t)5Li(g.s.) reaction was investigated at incident energies of 120, 160, and 200 MeV in order to resolve discrepancies found between previous measurements and theoretical predictions for the analogous reaction 4He(α,3He)5He(g.s.) at these energies. The line shapes of the 5Li ground-state resonance in the measured triton energy spectra are well reproduced by distorted-wave Born approximation (DWBA) calculations. Cluster-core optical potentials, which yield better overall agreement both for α-α elastic scattering and for the single-nucleon transfer reactions, are presented. It is shown that the previously observed discrepancies in magnitude between measured and calculated cross sections by a factor of ∼2 can be improved by employing spectroscopic factors obtained from a realistic shell model for the transitions to the final mass-3 and mass-5 systems.