Ground-state and single-particle energies of nuclei around ¹⁶O, ⁴⁰Ca, and ⁵⁶Ni from realistic nucleon-nucleon forces

We perform ab initio calculations for nuclei around ^{16}O, ^{40}Ca, and ^{56}Ni using realistic nucleon-nucleon forces. In particular, ^{56}Ni is computed as the heaviest nucleus in this kind of ab initio calculation. Ground-state and single-particle energies including three-body-cluster effects are obtained within the framework of the unitary-model-operator approach. It is shown that the CD-Bonn nucleon-nucleon potential gives quite good results close to the experimental values for all nuclei in the present work.