BARRIER DISTRIBUTIONS AS A TOOL TO INVESTIGATE FUSION AND FISSION

The recent availability of precisely measured fusion cross-sections ha s enabled the extraction of a representation of the distribution of ba rriers encountered during fusion. These representations, obtained from a variety of reactions, provide a direct observation of how the struc ture of the fusing nuclei changes the inter-nuclear potential landscap e, thus affecting the fusion probability. Recent experiments showing t he effects of static quadrupole and hexadecapole deformation, single-a nd double-phonon states, transfer of nucleons between two nuclei, and high-lying excited states are reviewed. The application of these conce pts to the explanation of the anomalous fission-fragment anisotropies observed following reactions with actinides is discussed.