| Two aspects of nuclear fusion of asymmetric systems near the Coulomb barrier are studied. First, the use of the interacting boson model (IBM) to account for target structure effects in subbarrier fusion is described. Calculations of cross sections, average angular momenta, and barrier distributions for target nuclei of various structures are compared with data. Second, the relation between moments of fusion cross sections and averages of angular momenta is examined. The roles of the centrifugal barrier and the target deformation in determining the effective barrier radius are clarified. A method for extracting average angular momentum from fusion cross sections is demonstrated using numerical calculations as well as data. |
