Charge radii, moments, and masses of mercury isotopes across the N=126 shell closure

Combining laser spectroscopy in a Versatile Arc Discharge and Laser Ion Source (VADLIS) with Penning-trap mass spectrometry at the CERN-ISOLDE facility, this work reports on mean-square charge radii of neutron-rich mercury isotopes across the N = 126 shell closure, the electromagnetic moments of 207Hg, and more precise mass values of 206-208Hg. The odd-even staggering (OES) of the mean square charge radii and the kink at N = 126 are analyzed within the framework of covariant density functional theory (CDFT), with comparisons between different functionals to investigate the dependence of the results on the underlying single-particle structure. The observed features are defined predominantly in the particle-hole channel in CDFT, since both are present in the calculations without pairing. However, the magnitude of the kink is still affected by the occupation of the nu 1i11/2 and nu 2g9/2 orbitals with a dependence on the relative energies as well as pairing.

Automated summary

By combining laser spectroscopy in a Versatile Arc Discharge and Laser Ion Source (VADLIS) with Penning-trap mass spectrometry at the CERN-ISOLDE facility, this study investigated neutron-rich mercury isotopes near the N = 126 shell closure. The odd-even staggering of mean square charge radii and the kink at N = 126 were analyzed within the covariant density functional theory (CDFT) framework, revealing their dependence on the particle-hole channel. The results suggest that the observed features are predominantly influenced by the occupation of specific orbitals and their relative energies.