Proton-induced reactions on He-6 at low energies - art. no. 044608

Finite-range coupled channel calculations of proton-induced reactions on He -6 have been performed below the He-6 three-body breakup threshold, assumin g that the alpha particle core is inert. The coupling scheme included all t ransitions between open channels and therefore no imaginary parts of the in teraction potentials were used. The calculations have revealed a complicate d dynamics of the p + He-6 interaction at the chosen energy, with couplings to all open channels being important to generate the final cross sections. The total absorption from the elastic p + He-6 channel depends on the deta ils of the interactions employed in the three-body model of He-6 and shows a strong correlation with the r.m.s. radius of He-6. The role of the exchan ge mechanisms was investigated within the framework of the distorted-wave B orn approximation. It was found that both the triton exchange He-6(p,He-4)t and two-neutron He-6(p,t)He-4 direct transfer mechanisms produce comparabl e cross sections. The investigation of the radiative capture He-6(p,gamma)L i-7 in the potential model shows strong suppression of the E1 transition be cause of the destructive interference between the external and internal con tributions to the reaction amplitude and the absorption in the incident cha nnel.