The effect of breakup in the fusion cross section in terms of suppression versus enhancement, discussed in a conflicting way in the literature, is addressed. Data and theoretical predictions ...available in the literature are compared. Excitation functions of the sub- and near-barrier fusion cross-sections for a wide variety of light and heavy systems are presented and interpreted. We have measured fusion excitation functions and breakup correlation functions for the medium weight systems 6Li + 59Co and 7Li + 59Co. These measurements help to establish the influence of the projectile breakup on the fusion process at near-barrier energies and contribute to the determination of how the mass of the target affects the breakup role. The results indicate a light fusion enhancement at sub-barrier energies and a geometry dominated cross section at barrier energies.
Are hot light nuclei liquid droplets? Szanto de Toledo A; Szanto, EM; Wotfe, M ...
Physical review letters,
04/1993, Volume:
70, Issue:
14
Journal Article
Peer reviewed
The mass distributions from the sequential decay of the compound nuclei formed by the sup 10B+sup 9Be and sup 10B+sup 10B reactions at ital Esub labcongruent11ital A MeV show no evidence of nuclear ...structure effects. We thus conclude that hot composite systems as light as sup 19F and sup 20Ne can behave like liquid droplets with no remnant shell effects.
In this work, angular distribution measurements for the elastic channel were performed for the 9Be+12C reaction at the energies ELab=13.0, 14.5, 17.3, 19.0 and 21.0 MeV, near the Coulomb barrier. The ...data have been analyzed in the framework of the double folding São Paulo potential. The experimental elastic scattering angular distributions were well described by the optical potential at forward angles for all measured energies. However, for the three highest energies, an enhancement was observed for intermediate and backward angles. This can be explained by the elastic transfer mechanism. Keywords: 9Be+12C, Elastic Scattering, Sãoo Paulo Potential.
Mass-energy and angular distributions of fission fragments for the {sup 48}Ca+{sup 144,154}Sm{yields}{sup 192,202}Pb, {sup 40}Ca+{sup 154}Sm{yields}{sup 194}Pb reactions have been measured. Fusion ...suppression and the presence of quasifission at energies near and below the Coulomb barrier have been observed for the reactions with the deformed target {sup 154}Sm. In the case of the spherical {sup 144}Sm target no evidence of quasifission has been found. Quasifission cross sections have been extracted from total fission-like events by analysis of their mass and angular distributions.
An experimental overview of reactions induced by the stable, but weakly-bound nuclei 6Li, 7Li and 9Be, and by the exotic, halo nuclei 6He, 8He, 8B, and 11Be on medium-mass targets, such as 58Ni, 59Co ...or 64Zn, is presented. Existing data on elastic scattering, total reaction cross sections, fusion processes, breakup and transfer channels are discussed in the framework of a CDCC approach taking into account the breakup degree of freedom.
Fusion cross section excitation functions were measured for the 6;7Li+59Co systems (12 < Elab < 26 MeV)aiming the investigation of the effect of the breakup process on the fusion cross section. The ...experimental method consisted on the detection of gamma-rays from the evaporation residues. Coupled channels calculations have been performed for both systems. The comparison to the experimental results support the conclusion that there is neither supression nor enhancement at energies above the coulomb barrier. A slight enhancement at energies below the barrier is observed for the 6Li+59Co cross section over the one for 7Li+59Co. In order to better quantify the effect of the breakup process, coincidence measurements for the breakup products are being performed.
An experimental overview of reactions induced by the stable, but weakly-bound nuclei 6Li, 7Li and 9Be, and by the exotic, halo nuclei 6He, 8B, 11Be and 17F on medium-mass targets, such as 58Ni, 59Co ...or 64Zn, is presented. Existing data on elastic scattering, total reaction cross sections, fusion processes, breakup and transfer channels are discussed in the framework of a CDCC approach taking into account the breakup degree of freedom.
alpha-d coincidence data were studied for the 6Li + 59Co reaction at E(lab) = 29.6 MeV. By using a kinematic analysis, it was possible to identify which process, leading to the same final state, has ...the major contribution for each of the selected angular regions. Contributions of the 6Li sequential and direct breakup to the incomplete fusion/transfer process were discussed by considering the lifetimes obtained by using a semiclassical approach, for both breakup components.