Advances in the Shell-Model Description of Weakly Bound and Unbound Nuclear States

We report on recent advances in the description of weakly bound and unbound nuclear states using either a real ensemble representing (quasi-)bound single-particle states and non-resonant continuum states (the so-called Shell Model Embedded in the Continuum) or a complex Berggren ensemble representing bound single-particle states, decaying resonant states, and non-resonant continuum states (the so-called Gamow Shell Model). These two different strategies in formulating the multiconfigurational Continuum Shell Model are illustrated by showing how the non-resonant continuum impacts the mechanism of nuclear binding.