Clustering in light nuclei and their effects on fusion and pre-equilibrium processes

• Published in: Nucleus no. 63; pp. 12 - 18
• Main Authors: Fabiana Gramegna, Magda Cicerchia, Tommaso Marchi, Marco Cinausero, Daniela Fabris, Giorgia Mantovani, Gianmaria Collazuol, Daniele Mengoni, Meltem Degerlier, Luca Morelli, Mauro Bruno, Michela D’Agostino, Sandro Barlini, Maurizio Bini, Alberto Camaiani, Gabriele Pasquali, Silvia Piantelli, Giovanni Casini, Giuseppe Pastore, Diego Gruyer, Pietro Ottanelli, Simone Valdrè, Nicla Gelli, Alessandro Olmi, Giacomo Poggi, Ivano Lombardo, Daniele Dell’aquila, Silvia Leoni, Natalja Cieplicka-Orynczak, Bogdan Fornal, Maria Colonna, Akira Ono
• Format: Journal Article
• Language: English
• Published: Centro de Gestión de la Información y Desarrollo de la Energía (CUBAENERGIA) 01-02-2019
• Subjects: datos experimentales; espectros de energía; núcleos ligeros; reacciones de iones pesados; teoría de hauser-feshbach
• ISSN: 0864-084X; 2075-5635

The study of heavy ion nuclear reactionis an important tool to observe and disentangle different and competing mechanisms, which may arise in the different energy regimes. In particular, at relatively low bombarding energy, it is quite interesting the comparison between pre-equilibrium and thermal emission of light charged particles from hot nuclear systems [1-6]. Indeed, the nuclear structure of the interacting partners can be strongly correlated to the dynamics, especially at energies close to the Coulomb barrier, and this effect emerges when some nucleons or clusters of nucleons are either emitted or captured. In particular, a major attention has been devoted, in the last years, to the possible observation of cluster structure effects in the competing nuclear reaction mechanisms, especially when fast processes are involved. At this purpose, the four reactions 16O+30Si at 111 MeV, 16O+30Si at 128 MeV, 18O+28Si at 126 MeV, 19F+27Al at 133 MeV have been measured to study the onset of pre-equilibrium in an energy range where, for central collisions, complete fusion is expected to be the predominant mode. Experimental data were collected using the GARFIELD + RCo array [7], fully equipped with digital electronics at the LegnaroNational Laboratories. The comparison between experimental data and different model predictions have been performed: in particular, both dynamical models based either on Stochastic Mean Field (TWINGO) or Anti-symmetrized Molecular Dynamics and fully statistical models (GEMINI++) have been considered. Simulated events are filtered through a software replica of the apparatus, to take into account all possible distortions of the experimental distributions due to the finite size of the apparatus.