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The purpose of this thesis is to report on the analysis done on the four reactions: 16O+30Si, 18O+28Si and 19F+27Al at 7 MeV/u e 16O+30Si at 8MeV/u, which have been measured at Legnaro National Laboratories with the GARFIELD+RCo detectors array. The idea behind this experiment is to evaluate the properties of the pre-equilibrium emission process in an energy regime close to the onset of such emission with the future project to carry out a following experiment of the same systems at higher bombarding energies, where the pre-equilibrium component is well assessed and may play a more important role. This experiment finds employment in the wider framework of an extensive research campaign on pre-equilibrium emission of light charged particles from hot nuclei made by the NUCLEX collaboratio. The study of pre-equilibrium emitted particles is a useful tool to examine nuclear clustering analyzing the effects of possible cluster structures on the nuclear reactions. After a theoretical and experimental introduction, the main analysis results are described: the quasi-complete events and complete events analysis; the study of selected evaporation residue channels; the evaluation of quantitative observables (BR and Q-value) of the major populated channels; the characterization of specific multiple (1, 2 and 3) alpha-channels.

The reaction 6He+64Zn was studied in order to investigate the effects of the projectile neutron-halo structure on the reaction mechanism at energies around the Coulomb barrier. Elastic scattering angular distributions, transfer/break-up angular distributions and fusion excitation functions have been measured. Due to the low recoil energy of the evaporation residues and the low intensity of the 6He beam, the fusion cross-section was measured by detecting off-line the atomic X-ray emission which follows the Electron Capture decay of the evaporation residues. For comparison the reaction 4He+64Zn was studied using the same technique. The data for the reaction 6He+64Zn show that the transfer and break-up mechanisms account for almost 80% of the total reaction cross-section, moreover we do not observe an enhancement of the fusion cross-section when compared with the 4He+64Zn reaction.

The elastic scatterin, neutron transfer and projectile break-up channels have been studied for the reaction 6He+64Zn at energies around the Coulomb barrier. The results show a very large break-up and transfer cross-section corresponding to the largest fraction of the total reaction cross-section. No evidence of threshold anomaly emerged from the elastic-scattering optical-model analysis.