The binary decay of very light nuclear systems into the ground state exit channel has been investigated for light heavy-ion collisions at energies ranging from the Coulomb barrier up to $\sim 4\hspace{0.5em}\mathrm{MeV}$ per nucleon. A systematic analysis of 14 reactions and up to 50 angular distributions allowed the extraction of the energy thresholds ${(E}_{\mathrm{ef}})$ for the fission channel forming the final products at the ground state (“elastic fission”). A significant suppression of the contribution of statistical processes is observed when the size of the system is reduced. This effect may be related to a relative increase of the fast and peripheral yields.

• Received 7 July 1999

DOI:https://doi.org/10.1103/PhysRevC.60.067602