Double-folding model potential forLi6scattering withHe4: Absence of anomalous reduction factor

A microscopic ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ ${+}^4$He interaction potential has been constructed in a double-folding model with the M3Y interaction and a single-nucleon-exchange term. Elastic scattering calculations with this potential together with a deuteron exchange mechanism reproduce the α${+}^6$Li elastic-scattering data at 36.6, 50, and 166 MeV in the forward- and back-angle regions, without any reduction factor. The exchange mechanism explains the large back-angle cross sections without affecting the forward-angle predictions. A recently formulated microscopic potential of Kamal et al. is also found to give a good fit to the forward-angle data at 36.6 and 50 MeV without renormalization. The latter however fails at 166 MeV. Inclusion of the deuteron exchange mechanism in the potential of Kamal et al. is also necessary to account for the large back-angle cross sections. The significance of the results in the context of the ${}_{}{}^6{}_{}{}^{}\mathrm{Li}$ target breakup reactions recently studied at low relative fragment energies is discussed.