G. P. A. Nobre

Elastic, inelastic scatterings and transfer reactions for 16,18O on 58Ni described by the São Paulo potential

We have used a parameter - free potential, obtained from data analysis at sub-barrier energies, to explain our measurements of elastic and several inelastic scattering cross sections for the 16,18O + 58Ni systems at an energy above the barrier. The data were analyzed through extensive coupled-channel calculations. Transfer cross sections could also be explained by the same interaction, which is consistent with the more fundamental Sao Paulo potential.

Effect on the heavy-ion fusion and elastic scattering cross sections of common approximations assumed in coupled-channel calculations

We study the effects of several approximations commonly used in coupled-channel analyses of fusion and elastic scattering cross sections. Our calculations are performed considering couplings to inelastic states in the context of the frozen approximation, which is equivalent to the coupled-channel formalism when dealing with small excitation energies. Our findings indicate that, in some cases, the effect of the approximations on the theoretical cross sections can be larger than the precision of the experimental data.

Coulomb and Nuclear Potentials Between Deformed Nuclei Applied to the Fusion Process

We obtained theoretical fusion cross sections based on a new and accurate procedure to calculate the Coulomb and nuclear interactions between deformed nuclei. The calculations were performed within the context of the barrier penetration model with zero point motion for the 64Ni + 64Ni system.

Comparison between the zero point motion and generalized frozen approximation models in accounting for heavy-ion fusion data

In recent papers, we have proposed two different models to calculate fusion cross sections for heavy-ion systems, based on coupled-channels calculations involving harmonic vibrations of the nuclear densities. The parameter-free Sao Paulo potential is assumed as the bare interaction and, therefore, the calculations are performed without any adjustable parameter. In the present work, we compare the results of these models in accounting for fusion data of approximately 60 different systems.

{sup 18}O+{sup 110}Pd: Measurements and realistic coupled-channel analysis in a transitional region

The inelastic, two-neutron and {alpha} transfer and quasielastic cross sections for the {sup 18}O+{sup 110}Pd system have been measured in the near barrier region (40 MeV {<=}E{sub lab}{<=}58 MeV). The experiments were performed in the Sao Paulo Pelletron laboratory. Coupled-channel analysis of the experimental data was performed using the Sao Paulo potential as a microscopic bare interaction. In the calculations, low-lying inelastic excitations, one- and two-neutron and {alpha} transfers to the target were considered as the main couplings, with no extra surface absorption. The agreement between the theoretical results and the experimental data is good. The role played by the coupled channels is very different in comparison with similar data analyses for the closed-shell region around {sup 58}Ni.