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Charge Radii Measurements of Exotic Tin Isotopes in the Proximity of and
Phys. Rev. Lett. 135, 222501 – Published 25 November, 2025
DOI: https://doi.org/10.1103/wbdx-k3cd
Abstract
We report nuclear charge radii for the isotopes , measured using two different collinear laser spectroscopy techniques at ISOLDE-CERN. These measurements clarify the archlike trend in charge radii along the isotopic chain and reveal an odd-even staggering that is more pronounced near the and shell closures. The observed local trends are well described by both nuclear density functional theory and valence space in-medium similarity renormalization group calculations. Both theories predict appreciable contributions from beyond-mean-field correlations to the charge radii of the neutron-deficient tin isotopes. The models, however, fall short of reproducing the magnitude of the known transition probabilities, highlighting the remaining challenges in achieving a unified description of both ground-state properties and collective phenomena.
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