APS : In-gas laser ionization and spectroscopy of actinium isotopes near the $N=126$ closed shell

The in-gas laser ionization and spectroscopy (IGLIS) technique was applied on the Ac212-215 isotopes, produced at the Leuven Isotope Separator On-Line (LISOL) facility by using the in-gas-cell and the in-gas-jet methods. The first application under on-line conditions of the in-gas-jet laser spectroscopy method showed a superior performance in terms of selectivity, spectral resolution, and efficiency in comparison with the in-gas-cell method. Following the analysis of both experiments, the magnetic-dipole moments for the (212-215)Acisotopes, electric-quadrupole moments and nuclear spins for the Ac-214,Ac-215 isotopes are presented and discussed. A good agreement is obtained with large-scale nuclear shell-model calculations by using a Pb-208 core.