The inclusive breakup for the 11 Li þ 208 Pb reaction at energies around the Coulomb barrier has been measured for the first time. A sizable yield of 9 Li following the 11 Li dissociation has been observed, even at energies well below the Coulomb barrier. Using the first-order semiclassical perturbation theory of Coulomb excitation it is shown that the breakup probability data measured at small angles can be used to extract effective breakup energy as well as the slope of BðE1Þ distribution close to the threshold. Fourbody continuum-discretized coupled-channels calculations, including both nuclear and Coulomb couplings between the target and projectile to all orders, reproduce the measured inclusive breakup cross sections and support the presence of a dipole resonance in the 11 Li continuum at low excitation energy.

The very neutron-rich oxygen isotopes 25

The current evaluation of the triple-reaction rate assumes that the decay of the 7.65 MeV, 0 þ state in 12 C, commonly known as the Hoyle state, proceeds sequentially via the ground state of 8 Be. This assumption is challenged by the recent identification of two direct -decay branches with a combined branching ratio of 17ð5Þ%. If correct, this would imply a corresponding reduction in the triple-reaction rate with important astrophysical consequences. We have used the 11 Bð 3 He; dÞ reaction to populate the Hoyle state and measured the decay to three particles in complete kinematics. We find no evidence for direct -decay branches, and hence our data do not support a revision of the triple-reaction rate. We obtain an upper limit of 5 Â 10 À3 on the direct decay of the Hoyle state at 95% C.L., which is 1 order of magnitude better than a previous upper limit.

The β-delayed neutron emission probabilities of neutron rich Hg and Tl nuclei have been measured together with β-decay half-lives for 20 isotopes of Au, Hg, Tl, Pb, and Bi in the mass region N≳126. These are the heaviest species where neutron emission has been observed so far. These measurements provide key information to evaluate the performance of nuclear microscopic and phenomenological models in reproducing the high-energy part of the β-decay strength distribution. This provides important constraints on global theoretical models currently used in r-process nucleosynthesis.

Rare isotope beams of neutron-deficient 106,108,110Sn from the fragmentation of 124Xe were employed in an intermediate-energy Coulomb excitation experiment. The measured B(E2,0(1)(+)-->2(1)(+)) values for 108Sn and 110Sn and the results obtained for the 106Sn show that the transition strengths for these nuclei are larger than predicted by current state-of-the-art shell-model calculations. This discrepancy might be explained by contributions of the protons from within the Z = 50 shell to the structure of low-energy excited states in this region.