Six-Nucleon Spectroscopy from a Realistic Nonlocal Hamiltonian

We apply the ab initio no-core nuclear shell model to solve the six-nucleon systems, ${}^6\mathrm{Li}$ and ${}^6\mathrm{He}$, interacting by realistic nucleon-nucleon ( $\mathrm{NN}$) potentials. In particular, we present the first results for $A=6\mathrm{}$ with the nonlocal CD-Bonn $\mathrm{NN}$ potential. The resulting ${}^6\mathrm{Li}$ binding energy $-29.3\mathrm{}\left(6\right)\mathrm{MeV}$ and the excitation spectra improve the agreement between the theory and experiment compared to results with local $\mathrm{NN}$ potentials, but the need for the inclusion of a real three-body interaction and/or further improvement of the $\mathrm{NN}$ forces remains. We predict properties of the ${}^6\mathrm{He}$ dipole modes, a subject of current controversy.