The elastic scattering of the radioactive halo nucleus 6He on 27Al target was measured at four energies close to the Coulomb barrier using the RIBRAS (Radioactive Ion Beams in Brazil) facility. The São Paulo Potential (SPP) was used and its diffuseness and imaginary strength were adjusted to fit the elastic scattering angular distributions. Reaction cross-sections were extracted from the optical model fits. The reduced reaction cross-sections of 6He on 27Al are similar to those for stable, weakly bound projectiles as 6,7Li, 9Be and larger than stable, tightly bound projectile as 16O on 27Al

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The elastic scattering of 6 He on 120 Sn has been measured at four energies above the Coulomb barrier using the 6 He beam produced at the RIBRAS (Radioactive Ion Beams in Brasil) facility. The elastic angular distributions have been analyzed with the optical model and three-and four-body continuum-discretized coupled-channels calculations. The total reaction cross sections have been derived and compared with other systems of similar masses.

The collision 6 He + 120 Sn has been investigated at four energies near the Coulomb barrier. A large yield of α particles has been detected, with energies around the energy of the scattered 6 He beam. The energy and angular distributions of the α particles have been analyzed and compared with breakup and neutron transfer calculations.

The dissociation of halo nuclei through their collision with light and heavy targets is considered within the Continuum Discretized Coupled Channels theory. We study the one-proton halo nucleus 8 B and the one-neutron halo nucleus 11 Be, as well as the more normal 7 Be. The procedure previously employed to extract the Coulomb dissociation cross section by subtracting the nuclear one is critically assessed, and the scaling law usually assumed for the target mass dependence of the nuclear breakup cross section is also tested. It is found that the nuclear breakup cross section for these very loosely bound nuclei does indeed behave as a + bA 1/3 . However, it does not have the geometrically inspired form of a circular ring which seems to be the case for normal nuclei such as 7 Be. We find further that we cannot ignore Coulomb-nuclear interference effects, which may be constructive or destructive in nature, and so the errors in previously extracted B(E1) using the subtraction procedure are almost certainly underestimated.