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Elastic scattering angular distributions for the weakly bound nucleus $^{7}\mathrm{Li}$ on $^{64}\mathrm{Zn}$ have been measured in a wide angular range at energies around the Coulomb barrier. The present experimental data and our previously measured elastic scattering data for the system $^{6}\mathrm{Li}+^{64}\mathrm{Zn}$ have been analyzed within the continuum-discretized coupled-channels method, where the resonant and nonresonant states of the projectile are taken into account. In this theoretical framework, we have also analyzed our previously measured excitation functions of elastic scattering at backward angles and the corresponding barrier distributions for the same systems. A good agreement between the experimental data and the calculations has been observed. The obtained results, besides confirming the importance of the coupling to the breakup channels in collisions with weakly bound nuclei, show that, in the case of $^{6}\mathrm{Li}$, the inclusion of the resonant states of the projectile produces non-negligible effects.

Excitation functions for the production of heavy residues have been measured for the collisions ${}^{6,7}\mathrm{Li}+{}^{64}\mathrm{Zn}$ at energies around and below the Coulomb barrier. The cross sections for heavy residue production have been measured using an activation technique, detecting off-line the characteristic atomic x-rays emitted in the electron capture decay of the reaction products. The experimental relative yields of the residues have been compared with statistical model calculations performed by using the code cascade. Such a comparison suggests that heavy residue production is dominated by complete fusion at above-barrier energies, whereas different processes like incomplete fusion and/or transfer become dominant in the sub-barrier energy region. The heavy residue excitation function ratio between the ${}^{6}$Li- and ${}^{7}$Li-induced collisions shows an increasing trend as the energy decreases below the barrier.

We have measured the excitation functions of several reactions occurring in the fusion of $^{12}\mathrm{C}$ with $^{103}\mathrm{Rh}$ at incident energies up to about 230 MeV. The data can be satisfactorily reproduced by considering the preequilibrium emission of particles during the thermalization of the composite nucleus. The energy evolution of the mean-field interaction is also discussed. \textcopyright{} 1996 The American Physical Society.

The excitation functions for production of nineteen isotopes of At, Po, Bi, Pb, and Tl in the interaction of $^{12}\mathrm{C}$ with $^{197}\mathrm{Au}$ between 57 and 97 MeV incident energy have been measured with the activation technique. The analysis of these data allows one to estimate the cross sections for complete fusion of $^{12}\mathrm{C}$ and incomplete fusion of $^{8}\mathrm{Be}$ and \ensuremath{\alpha} fragments with gold, and shows the presence of preequilibrium emissions at incident energies only slightly higher than the Coulomb barrier acting between $^{12}\mathrm{C}$ and $^{197}\mathrm{Au}$.