Transfer and/or breakup modes in the 6He+209Bi reaction near the Coulomb barrier

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