NUTELAS · NUclear sTructure Evolution with LAser Spectroscopy

The study of exotic atomic nuclei with extreme proton to neutron asymmetry is one of the pillars of contemporary nuclear physics and the study of the evolution of fundamental nuclear properties across the nuclear chart is one of its key aspects. In the last decades, many experimental and theoretical efforts have been devoted to the study of the disappearance of shell closures, often accompanied by an increase of configuration mixing and collectivity, leading to the formation of islands of inversion, where ground-states are found to have a deformed structure. The experimental study of such regions is of crucial importance for our understanding of the low-lying mechanisms generating these drastic structural evolutions, which poses serious challenges to nuclear theories. Ground-state properties are known to be a very sensitive probes to the nuclear wave function and to provide stringent test to nuclear theories. The Collinear Resonance Ionization Spectroscopy (CRIS) experiment is a cutting-edge experimental setup located at ISOLDE/CERN, that perform laser spectroscopy on radioactive atomes in order to extract ground state properties. The present project aims at pushing ground-state nuclear properties measurements into the region of the N=40 island of inversion and near 78Ni, in order to benchmark nuclear theories (shell model, density functional theory and ab-initio) and to shed light on the low-lying mechanism responsible for drastic structural evolutions. Among the objectives of the project is the implementation of a decay spectroscopy station at CRIS that will allow to combine decay and laser spectroscopy techniques. This will offer unique opportunities for nuclear structure studies in the 78Ni region and has the potential to lead to several crucial discoveries.