Ab initio many-body calculations of nucleon-nucleus scattering

We develop a new ab initio many-body approach capable of describing simultaneously both bound and scattering states in light nuclei, by combining the resonating-group method with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters. This approach preserves translational symmetry and the Pauli principle. We outline technical details and present phase-shift results for neutron scattering on H-3, He-4, and Be-10 and proton scattering on He-3,He-4, using realistic nucleon-nucleon (N N) potentials. Our A = 4 scattering results are compared to earlier ab initio calculations. We find that the CD-Bonn N N potential in particular provides an excellent description of nucleon-He-4 S-wave phase shifts. In contrast, the experimental nucleon-He-4 P-wave phase shifts are not well reproduced by any N N potential we use. We demonstrate that a proper treatment of the coupling to the n-Be-10 continuum is successful in explaining the parity-inverted ground state in Be-11.