Special Features of Nuclear Reactions Involving Loosely Bound Cluster Nuclei

Abstract

Reactions involving loosely bound nuclei have many special features. An enhancement of interaction cross sections in the subbarrier energy region is one of them. This effect is pronounced for nuclei that have a cluster structure. Transfer and complete-fusion reactions are dominant interaction channels for them. Experimental data on the cross sections for fusion reactions induced by such nuclei deviate strongly from the predictions of the statistical compound-nucleus model at energies in the vicinity of the Coulomb barrier. Also, the cross sections for neutron transfer from ^3,6,8He and deuteron transfer from ^6,9Li were found to grow at deep subbarrier energies. These results are discussed from the point of view of the effect of the cluster structure of nuclei on the probability for their interaction at energies in the vicinity of the Coulomb barrier. A theoretical analysis of relevant experimental data was performed with allowance for the effect of outer neutrons and clusters in loosely bound nuclei of bombarding particles. The results of the present study may be used to solve some problems of astrophysics—in particular, to obtain deeper insight into the mechanism of the production of light elements in the Universe.