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arXiv · 2208.03037

Electroweak nuclear radii constrain the isospin breaking correction to $V_{ud}$

Chien-Yeah Seng·Mikhail Gorchtein
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Abstract

We lay out a novel formalism to connect the isospin-symmetry breaking correction to the rates of superallowed nuclear beta decays, $\delta_\text{C}$, to the isospin-breaking sensitive combinations of electroweak nuclear radii that can be accessed experimentally. We individuate transitions in the superallowed decay chart where a measurement of the neutron skin of a stable daughter even at a moderate precision could already help discriminating between models used to compute $\delta_\text{C}$. We review the existing experimental situation and make connection to the existing and future experimental programs.

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Chien-Yeah Seng, Mikhail Gorchtein. 2022-08-05. Electroweak nuclear radii constrain the isospin breaking correction to $V_{ud}$. https://doi.org/10.1016/j.physletb.2022.137654

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