Abstract :
Beams of 132,134Sn and 134Te were used to bombard a 64Ni target and measure fusion excitation functions near the Coulomb barrier. Fusion induced by 132,134Sn and 134Te below the barrier is enhanced as compared to stable Sn and Te beams. The enhancement in 132Sn and 134Te is essentially due to the larger radii which lower the Coulomb barriers. However, the enhancement in 134Sn induced fusion cannot be accounted for by the change in nuclear size.