STRONG COUPLED-CHANNEL EFFECTS IN THE BE-9(HE-3,HE-3), BE-9(HE-3,BE-7) AND (HE-3,LI-6) REACTIONS AT E(HE-3)=60 MEV

The angular distributions of the Be-9(He-3,Be-7)He-5 and Be-9(He-3,Li- 6)Li-6 reactions were measured at the energy of 60 MeV for the transit ions to the ground states of He-5 and Li-6 and 2.185 MeV (3(+)), 5.37 MeV (2(+)) + 5.65 MeV (1(+)) excited states of Li-6. The experimental data were analyzed using the coupled reaction channels (CRC) model inc luding one- and two-step cluster transfers and cluster spectroscopic a mplitudes calculated in the framework of the translation-invariant she ll model. It was found that the coupling with inelastic channels and r eorientation process modifies the elastic scattering cross section at large angles and allows one to describe the cross section satisfactori ly. The cluster transfers are unimportant. The Be-9(He-3,alpha)Be-8 re action was included in the analysis to determine the optical potential of the intermediate alpha + Be-8 channel in two-step transfer. It was found that in the Be-9(He-3,Be-7)He-5 reaction the alpha-transfer dom inates only at small angles while the transfer of the 2n-cluster at la rge angles, In the angular range theta(cm) similar or equal to 30 degr ees - 80 degrees the cross sections are determined by the sequential t ransfers of the neutron and He-3-cluster as well as deuteron and deute ron. The transitions to highly excited states of the intermediate Be-8 and Li-7 nuclei give large contributions to the cross sections. In th e Be-9(He-3,Li-6)Li-6 reaction the t-cluster transfer dominates only f or the transitions to the excited states of Li-6. The cross section fo r the transition to the ground state of Li-6 is determined by the sequ ential transfer of the neutron and deuteron. Good agreement between me asured and calculated cross sections was achieved.