Fusion of the most neutron-rich nucleus He: Recent results from GANIL

Re-accelerated radioactive ions beams of He from the SPIRAL facility at GANIL have been used to perform the first experimental investigations at energies around the Coulomb barrier of fusion and direct reactions with the most neutron rich He. Two experiments (in the He+Cu and He+Au systems) have been performed, using the complementarity of in-beam and off-beam techniques, to measure integral and differential cross sections for elastic scattering, fusion and neutron(s) transfer. These results, compared with Coupled Reaction Channels calculations as well as phenomenological approaches allowed to probe and understand the different facets of the interplay between the intrinsic structure of He and reaction mechanisms.