Near-barrier fusion of Sn+Ni and Te+Ni systems: Examining the correlation between nucleon transfer and fusion enhancement

The fusion excitation functions for radioactive Sn132+Ni58 and stable Te130+Ni58,64 were measured at energies near the Coulomb barrier. The coupling of transfer channels in heavy-ion fusion was examined through a comparison of Sn+Ni and Te+Ni systems, which have large variations in the number of positive Q-value nucleon transfer channels. In contrast with previous experimental comparisons, where increased sub-barrier fusion cross sections were observed in systems with positive Q-value neutron transfer channels, the reduced excitation functions were equivalent for the different Sn+Ni and Te+Ni systems. The present results suggest a dramatically different influence of positive Q-value transfer channels on the fusion process for the Sn+Ni and Te+Ni systems.