Near- and sub-barrier fusion ofNi58withNi58

Differential cross sections for evaporation residue formation following the complete fusion of ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ with 187.6 to 220 MeV ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$ ions were measured with high precision using a velocity selector together with a counter telescope. The resulting cross sections for complete fusion ranged in magnitude from 50 μb at 93.3 MeV to 230 mb at 108.9 MeV (c.m.). The cross sections for complete fusion at sub-barrier energies were shown to be far greater than those predicted by standard barrier penetration models.