Reaction Mechanisms of Exotic Nuclear Systems at Low Energies

Abstract

A transfer reaction method has been applied to extract the optical potentials of neutron-halo 6 He+ 12 C, 64 Zn and 209 Bi systems via the one-proton stripping reactions induced by 7 Li. The complete picture of threshold anomaly behavior has been obtained for the 6 He+ 209 Bi system. It is shown that the dispersion relation connecting the real and imaginary parts does not work for the exotic nuclear systems. Possible reasons are discussed, but further study is strongly desired to discover the underlying physics. Besides, reactions induced by proton-rich exotic nucleus 17 F on 58 Ni, 89 Y and 208 Pb targets have been measured at energies around the Coulomb barrier. Thanks to the use of a powerful detector array, the reaction products over a large Z range can be identified clearly. Angular distributions of elastic scattering have been obtained at present. Continuum-discretized coupled-channels calculations indicate that the breakup coupling effects are not significant. Further analyses are still in progress.