Ab-initio Gorkov-Green's function calculations of open-shell nuclei

Understand

We present results from a new ab-initio method that uses the self-consistent Gorkov Green's function theory to address truly open-shell systems.

• The formalism has been recently worked out up to second order and is implemented here in nuclei for the first time on the basis of realistic nuclear forces.
• We find good convergence of the results with respect to the basis size in Ca44 and Ni74 and discuss quantities of experimental interest including ground-state energies, pairing gaps and particle addition/removal spectroscopy.
• These results demonstrate that the Gorkov method is a valid alternative to multireference approaches for tackling degenerate or near degenerate quantum systems.