No abstract

In the past decade, coupled-cluster theory has seen a renaissance in nuclear physics, with computations of neutron-rich and medium-mass nuclei. The method is efficient for nuclei with product-state references, and it describes many aspects of weakly bound and unbound nuclei. This report reviews the technical and conceptual developments of this method in nuclear physics, and the results of coupled-cluster calculations for nucleonic matter, and for exotic isotopes of helium, oxygen, calcium, and some of their neighbors.

With the goal of developing predictive ab-initio capability for light and medium-mass nuclei, twonucleon and three-nucleon forces from chiral effective field theory are optimized simultaneously to low-energy nucleon-nucleon scattering data, as well as binding energies and radii of few-nucleon systems and selected isotopes of carbon and oxygen. Coupled-cluster calculations based on this interaction, named NNLOsat, yield accurate binding energies and radii of nuclei up to 40 Ca, and are consistent with the empirical saturation point of symmetric nuclear matter. In addition, the low-lying collective J π = 3 − states in 16 O and 40 Ca are described accurately, while spectra for selected p-and sd-shell nuclei are in reasonable agreement with experiment. Introduction -Interactions from chiral effective field theory (EFT) [1][2][3][4] and modern applications of renormalization group techniques [5][6][7][8] have opened the door for a description of atomic nuclei consistent with the underlying symmetries of quantum chromodynamics, the theory of the strong interaction. Chiral nuclear forces can be constructed systematically from long-range pion physics augmented by contact interactions. Over the past decade, the renaissance of nuclear theory based on realistic nuclear forces and powerful computational methods has pushed the frontier of ab initio calculations from fewbody systems and light nuclei [6, 9, 10] to medium-mass nuclei [11][12][13][14][15][16][17][18][19].