Energy dependence of the nucleus-nucleus interaction in the Be-9+C-12 system and the Be-9 reorientation

The angular distributions of elastic and inelastic scattering of the C-12 i ons on the Be-9 nuclei were measured using the Kiev U-240 cyclotron at the beam energy 65 MeV for the transitions to the ground state of the C-12 nucl eus and to the ground, 1.68 MeV and 2.43 MeV excited states of the Be-9 nuc leus. These data and elastic scattering in the Be-9 + C-12 system in the en ergy range of E-cm = 5.14-90.46 MeV were analyzed within the optical and co upled reaction channel (CRC) models. The elastic and inelastic scattering, transfer reactions and spin reorientation of the 9Be nucleus in the ground state were included in the coupled channel scheme. The data of inelastic sc attering at E-lab(C-12)= 65 MeV were used to determine the deformation para meters of Be-9 nucleus in the ground state. It was found that the reorienta tion process dominates in the elastic scattering data at large angles. A go od description of all sets of experimental data was achieved. The energy de pendence of parameters for the real and imaginary parts of the optical pote ntial was analyzed using analytic forms of the Woods-Saxon type. The disper sion relation between the real and imaginary parts of the optical potential was applied in the analysis of the energy dependence. The parameters for t he energy dependence of the Be-9 + C-12 optical potential were determined. (C) 2000 Elsevier Science B.V. All rights reserved.