Some Insights into Cluster Structure of ⁹Be from ³He + ⁹Be Reaction

Abstract

The study of inelastic scattering and multi-nucleon transfer reactions was performed by bombarding a 9 Be target with a 3 He beam at the incident energy of 30 MeV. Angular distributions for 9 Be( 3 He, 3 He) 9 Be, 9 Be ( 3 He, 3 He) 8 Be, 9 Be ( 3 He, 7 Be) 5 He, 9 Be ( 3 He, 6 Li) 6 Li and 9 Be ( 3 He, 7 Li) 5 Li reaction channels were measured. Experimental angular distributions for the corresponding ground states (g.s.) were analyzed within the framework of the optical model, the coupled-channel approach and the distorted-wave Born approximation. Cross sections for channels leading to unbound 5 He g.s ., 5 Li g.s. and 8 Be systems were obtained from singles measurements where the relationship between the energy and the scattering angle of the observed stable ejectile was constrained by two-body kinematics. Information on the cluster structure of 9 Be was obtained from the transfer channels. It was concluded that cluster transfer was an important mechanism in the investigated nuclear reaction channels. In the present work an attempt was made to estimate the relative strengths of the interesting (n + 8 Be) and (α + 5 He) cluster configurations in 9 Be. The contributions of different exit channels have been determined confirming that the (α + 5 He) configuration plays an important role. The configuration of 8 Be consisting of two bound helium clusters ( 5 He + 6 He) is significantly suppressed, whereas the two-body configurations (n + 8 Be) and (α + 5 He) including unbound 8 Be and 5 He are found more probable.