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arXiv · 2212.02681

Model-independent determination of nuclear weak form factors and implications for Standard Model precision tests

Chien-Yeah Seng
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Abstract

We analyze the recoil corrections in superallowed beta decays of $T=1$, $J^P=0^+$ nuclei by fixing the mean square charge weak radius model-independently using the data of multiple charge radii across the nuclear isotriplet. By comparing to model estimations, we argue that the existing theory uncertainty in the statistical rate function $f$ might have been substantially underestimated. We discuss the implications of our proposed strategy for precision tests of Standard Model, including a potential alleviation of the first-row CKM unitarity deficit, and motivate new experiments for charge radii measurements.

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Chien-Yeah Seng. 2022-12-06. Model-independent determination of nuclear weak form factors and implications for Standard Model precision tests. https://doi.org/10.1103/physrevlett.130.152501

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