Peripheral fragmentation of a 287 MeV/nucleon beam of the halo nucleus ${}^{11}\mathrm{Li}$ incident on a carbon target has been studied in a fragment-neutron coincidence experiment. The momentum distribution of the ${}^{10}\mathrm{Li}$ fragments gives access to the momentum distribution of the removed neutron in ${}^{11}\mathrm{Li}$. From the shape of the distribution, the $({1s}_{1/2}{)}^2$ contribution to the mixture of $({1s}_{1/2}{)}^2$ and $({0p}_{1/2}{)}^2$ components in the ground-state wave function was determined to be $(45\pm 10)\%$. The angular correlation between the knocked out neutron and the one from the decay of ${}^{10}\mathrm{Li}$ shows a skew distribution signaling interference of these two different parity states.

Collisions induced by ${}^{9,10,11}\mathrm{Be}$ on a ${}^{64}\mathrm{Zn}$ target at the same c.m. energy were studied. For the first time, strong effects of the ${}^{11}\mathrm{Be}$ halo structure on elastic-scattering and reaction mechanisms at energies near the Coulomb barrier are evidenced experimentally. The elastic-scattering cross section of the ${}^{11}\mathrm{Be}$ halo nucleus shows unusual behavior in the Coulomb-nuclear interference peak angular region. The extracted total-reaction cross section for the ${}^{11}\mathrm{Be}$ collision is more than double the ones measured in the collisions induced by ${}^{9,10}\mathrm{Be}$. It is shown that such a strong enhancement of the total-reaction cross section with ${}^{11}\mathrm{Be}$ is due to transfer and breakup processes.

The elastic scattering of 6He on 208Pb has been measured at laboratory energies of 14, 16, 18 and 22 MeV. These data were analyzed using phenomenological Woods–Saxon form factors and optical model calculations. A semiclassical polarization potential was used to study the effect of the Coulomb dipole polarizability. Evidence for long range absorption, partially arising from Coulomb dipole polarizability, is reported. The energy variation of the optical potential was found to be consistent with the dispersion relations which connect the real and imaginary parts of the potential.status: publishe