Fully Microscopic Calculations for Closed-Shell Nuclei with Realistic Nucleon-Nucleon Potentials

The ground-state energy of the doubly magic nuclei 4He and 16O has been calculated within the framework of the Goldstone expansion starting from modern nucleon-nucleon potentials. A low-momentum potential V-low-k has been derived from the bare potential by integrating out its high-momentum components beyond a cutoff Lambda. We have employed a simple criterion to relate this cutoff momentum to a boundary condition for the two-nucleon model space spanned by a harmonic-oscillator basis. Convergence of the results has been obtained with a limited number of oscillator quanta.