Faddeev equations for the 6Li nucleus

The 6Li nucleus is considered as composed of an alpha-particle, a proton and a neutron. With this construction the 6Li nucleus is studied as a three-body problem. The Faddeev equations are given, by taking separable potentials for the interaction between the alpha, the proton and the neutron particles in pairs. The nucleon-nucleon potential is taken as a central term of the Yamaguchi type and also including a tensor force. To investigate the short-range correlations in this three-body system, the nucleon-nucleon potential is taken to include a repulsive soft-core part in addition to the attractive part considered. The nucleon-alpha potential is taken as central and spin-orbit terms which fit the corresponding experimental nucleon-alpha phase shifts. The effect of Coulomb forces between the proton and the alpha-particle is taken into account. By solving the coupled Faddeev equations numerically, the binding energies for the ground and excited states of 6Li are calculated. Inclusion of repulsive-core effects is found to change the results by 19%. (author)