Fusion of 6Li with 152Sm: Role of projectile breakup versus target deformation

Complete fusion cross sections for 6Li + 152Sm reaction have been measured at beam energies (Elab=20–40 MeV) near the Coulomb barrier. The sub-barrier fusion cross sections were found to be systematically larger than those for 6Li + 144Sm, as expected from the deformed shape of the 152Sm nucleus. The coupled-channels (CC) calculations including both projectile and target couplings overpredict the experimental fusion cross sections at above barrier energies. Reduced fusion cross sections for the present system at above barrier energies are found to be smaller compared to those with tightly-bound projectiles forming similar compound nuclei and also to those predicted using proximity potential. These observations along with the comparison of derived barrier distributions conclude that the complete fusion cross sections at energies above the Coulomb barrier are suppressed by 28±4%. A large cross section measured for incomplete fusion indicates that the above suppression is due to the loss of incident flux caused by projectile breakup. Thus the effect of both target deformation and projectile breakup are found to coexist.