Charge Radii and Magnetic Moments of Neutron-Rich Silicon Isotopes

This contribution will present the first laser resonance ionization spectroscopy measurements of neutron-rich silicon isotopes up to 38Si, performed at the newly commissioned Resonance Ionization Spectroscopy Experiment (RISE) at the BEOLA facility at the Facility for Rare Isotope Beams (FRIB). From the measured isotope shifts and hyperfine structures, the magnetic dipole moments of odd-N isotopes and changes in mean-square nuclear charge radii of 28-36,38Si were extracted.

With a proton sub-shell closure at Z=14, the silicon isotopic chain provides an important platform to probe the evolution of the nuclear shell structure and collectivity of medium mass nuclei [1,2], particularly near the proposed doubly magic nucleus 34Si. Of particular interest is the evolution of the nuclear charge radii across the number N=20, where a central depletion or bubble-like structure has been suggested in 34Si [3-7].

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