Reaction dynamics in clustered nuclear systems

This work is concerned with the theoretical study of nuclear reactions between light charged ions at incident energies around and below the reactants Coulomb barrier, with a focus on the energy range of astrophysical interest for Big Bang and quiescent stellar processes. The main goal of the analysis is to investigate the sensitivity of nuclear reaction dynamics, and more specifically the cross-section predictions, to the description of the structure of each reactant, and in particular to clustering phenomena. The case of the $^6$Li + p $\to$ $^3$He + $^4$He reaction was investigated explicitly, treating the process as a direct deuteron transfer in first- or second-order distorted-wave Born approximation and through a coupled-reaction-channels approach. The penetrability of the Coulomb barrier in the initial state was also analysed phenomenologically from available experimental data, and studied theoretically taking into account the $^6$Li ground-state deformation.Comment: PhD thesis (University of Catania and University of Seville, in joint supervision