Elastic scattering and breakup reactions of the proton drip-line nucleus 8 B on 208 Pb at 238 MeV

Elastic scattering and breakup angular distributions of the weakly bound radioactive nucleus 8 B on a 208Pb target at an incident energy of 238 MeV, which corresponds to four times the Coulomb barrier, have been measured at the HIRFL-RIBLL facility (Institute of Modern Physics, Lanzhou). The data have been analyzed using the optical model and the continuum discretized coupled channels (CDCC) formalism. The measured and calculated elastic scattering angular distributions do not show any significant Coulomb rainbow suppression. The angular distribution for the breakup reaction was measured for the first time at this energy. The angular distribution of the 7 Be fragments could be reproduced considering elastic plus nonelastic breakup contributions, with the former evaluated with the CDCC calculations and the latter with the model of Ichimura, Austern, and Vincent [Phys. Rev. C 32, 431 (1985)]. The comparison of the breakup cross section of 8 B with that of 11Be suggests that the Coulomb and centrifugal barriers encountered by the valence proton may suppress the breakup cross section.