Fusion, Breakup and Scattering of Weakly Bound Nuclei at Near Barrier Energies

ABSTRACT

We discuss experimental and systematic results in the field of reactions with weakly bound nuclei at near barrier energies, particularly fusion, breakup and elastic scattering. The influence of breakup channels on the complete fusion of weakly bound systems is investigated in comparison with the benchmark curve called the Universal Fusion Function and the derived systematic behavior of fusion cross sections of weakly bound nuclei is explained in terms of polarization potentials. The systematic enhancement of the cross section at sub-barrier energies is consistent with recent experimental observations that nucleon transfer, often leading to breakup, is dominant compared to direct breakup in this energy regime. At energies above the barrier, the repulsive polarization potential due to direct breakup predominates and complete fusion is suppressed. We also discuss the relative importance of nuclear and Coulomb breakup as a function of the target charge and the destructive interference between them.

Keywords:

Breakup reactions, elastic scattering, fusion reactions, halo nuclei, polarization potentials, transfer reactions, weakly bound nuclei.