DREB2014 - Direct Reactions with Exotic Beams

Elastic angular distributions of the 6He+120Sn and 6He+58Ni scatterings have been measured at energies slightly above the Coulomb barrier. Three and four-body continuum discretized coupled channels calculations have been performed. For the 6He+58Ni system, the three-body CDCC calculation underestimates the experimental cross sections in the intermediate angles region and the four-body calculation reproduces very well the data in the whole angular range of the measurements. In these CDCC calculations we folded realistic optical potentials of the n+target and alpha+target sub-systems, to bild the total 6He+target potential. No parameter adjustment has been performed and the results can be considered as predictions. Total reaction cross-sections have been obtained from the CDCC results and are compared with the cross sections for several stable systems. The total reaction cross section of the exotic system 6He+target are systematically larger than the weakly bound stable systems, such as 6Li+target. A large yield of alpha particles has been observed in the spectra of the 6He+120Sn collision, with velocities around the velocity of the projectile and, this alpha particle yield seems to account for the observed enhancement in the total reaction cross section.