'Nuclear charge radii of exotic Ag and Pd isotopes via laser spectroscopy'

by Sarina Geldhof (University of Jyvaskyla (FI))

Thursday 28 Jan 2021, 14:15 → 15:15 Europe/Zurich

CERN

High-resolution laser spectroscopy has been proven to be a powerful tool to extract nuclear structure data in an almost model-independent manner. The isotope shift which can be extracted from the hyperfine spectra of exotic nuclei gives direct access to changes in mean-square charge radii. This provides information on e.g. deformation and shape coexistence, proton-neutron pairing correlations, and the presence of nuclear shell closures. In recent years, measurements of nuclear charge radii have also been proven exceptionally potent in testing state-of-the-art nuclear Density Functional Theory (DFT) and ab-initio approaches. 

The Pd and Ag isotopes are located in a transitional area in the nuclear chart, in between the tin and yttrium regions, where there has been a gap in available optical spectroscopy data for radioactive nuclei, in particular for the Tc, Ru, Rh and Pd isotopes. This is in part due to the refractory character of these nuclei, which makes their production challenging for many facilities, but also due to their complex atomic structure.

At the IGISOL facility, these difficulties were overcome thanks to the chemical insensitivity of the ion-guide production method, the development of a hot cavity catcher laser ion source, and recent upgrades to the collinear laser spectroscopy beamline. Collinear laser spectroscopy was performed on neutron-rich and -deficient Pd isotopes and neutron-rich Ag isotopes, and in-source laser spectroscopy on neutron-deficient Ag isotopes. The measured nuclear charge radii will be presented, and the results will be compared to state-of-the-art DFT calculations using Fayans Energy Density Functionals.