Near-barrier fusion of weakly bound6Liand7Linuclei with59Co

Abstract

Excitation functions for sub- and near-barrier total (complete + incomplete) fusion cross sections are presented for the ${}^{6,7}\mathrm{Li}{+}^{59}\mathrm{Co}$ reactions. Evaporation residues were identified by their characteristic $\ensuremath{\gamma}$ rays and the corresponding yields measured with both the IReS Garel $+$ array at the Vivitron facility and with the S\~ao Paulo Ge array at the 8UD Pelletron tandem facility using standard \ensuremath{\gamma}-ray techniques. The data extend to medium-mass systems previous works exploring the coupling effects (hindrance versus enhancement) in fusion reactions of both lighter and heavier systems. The results indicate a small enhancement of total fusion for the more weakly bound ${}^{6}\mathrm{Li}$ at sub-barrier energies, with similar cross sections for both reactions at and above the barrier.