Transfer and/or breakup modes in the He-6+Bi-209 reaction near the Coulombbarrier

Reaction products from the interaction of He-6 with Bi-209 have been measur ed at energies near the Coulomb barrier. A He-4 group of remarkable intensi ty, which dominates the total reaction cross section, has been observed. Th e angular distribution of the group suggests that it results primarily from a direct nuclear process. it is likely that this transfer and/or breakup c hannel is the doorway state that accounts for the previously observed large sub-barrier fusion enhancement in this system.