Global approach for the reactions Be7+Si28 and Be7+Pb208 at near- and sub-barrier energies

Abstract

Elastic scattering, total reaction, and fusion cross section measurements for the radioactive $^{7}\mathrm{Be}$ nucleus on a light and a heavy target, are treated in a global approach at near and sub-barrier energies for probing the optical potential and describing fusion at low energies. Elastic scattering data of $^{7}\mathrm{Li}$ on the same target were analyzed under the same context to support this analysis. It is found that for low mass targets, dispersion relations are not adequate for describing the potential or the fusion. On the contrary this is possible for heavy targets, where the standard potential threshold anomaly and fusion enhancement is observed. The consequences of the above on fusion hindrance at deep sub-barrier energies is discussed.