2024/09/11 by L. Lalanne, M. Athanasakis-Kaklamanakis, Lalanne, L. +51 · 1 citation
Engineering · Physics and Astronomy · #Advanced X-ray Imaging Techniques #FOS: Physical sciences #Nuclear Experiment (nucl-ex) #Nuclear Theory (nucl-th) #Particle Accelerators and Free-Electron Lasers #Quantum and Classical Electrodynamics
paper · pdf · doi:10.48550/arxiv.2409.07324
openalex publication_date 2024/09/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
This paper reports on the measurement of the ground-state spin and nuclear magnetic dipole moment of 61Cr. The radioactive ion beam was produced at the CERN-ISOLDE facility and was probed using high-resolution resonance ionization laser spectroscopy with the CRIS apparatus. The present ground-state spin measurement I = (1)/(2), differing from the previously adopted I =((5)/(2)), has significant consequences on the interpretation of existing beta decay data and nuclear structure in the region. The structure and shape of 61Cr is interpreted with state-of-the-art Large-Scale Shell Model and Discrete-Non-Orthogonal Shell Model calculations. From the measured magnetic dipole moment μ(61Cr)=+0.539(7)~μN and the theoretical findings, its configuration is understood to be driven by 2 particle - 2 hole neutron excitations with an unpaired 1p1/2 neutron. This establishes the western border of the N=40 Island Of Inversion (IoI), characterized by 4 particle - 4 hole neutron components. We discuss the shape evolution along the Cr isotopic chain as a quantum phase transition at the entrance of the N=40 IoI.