Exotic neutron-rich medium-mass nuclei with realistic nuclear forces

We present the first application of the newly developed extended Kuo-Krenciglowa (EKK) theory of the effective nucleon-nucleon interaction to shell-model studies of exotic nuclei, including those where conventional approaches with fitted interactions encounter difficulties. This EKK theory enables us to derive an interaction that is suitable for several major shells (sd+pf in this work). By using such an effective interaction obtained from the Entem-Machleidt QCD-based χN3LO interaction and the Fujita-Miyazawa three-body force, the energies, E2 properties, and spectroscopic factors of low-lying states of neutron-rich Ne, Mg, and Si isotopes are nicely described, as the first shell-model description of the “island of inversion” without fit of the interaction. The long-standing question as to how particle-hole excitations occur across the sd−pf magic gap is clarified with distinct differences from the conventional approaches. The shell evolution is shown to appear similarly to earlier studies.status: publishe