Fusion Cross Section Limitation of the 7Li + 11B Reaction

The Li-7 + B-11 reaction has been studied in the energy range from 3.1 to 11.5 MeV in the c.m. system by measuring the cross section of the gamma-ray transitions in the residual nuclei produced. Statistical compound nucleus calculations have been performed in order to extract cross sections of the individual exit channels and eventually the fusion cross section. The hindrance of the fusion cross section at energies above the interaction barrier has been investigated in terms of macroscopic models.