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arXiv · 2508.15203

High-precision determination of radiative corrections to superallowed nuclear beta decays

Chien-Yeah Seng
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Abstract

Superallowed $0^+\rightarrow 0^+$ transitions between $T=1$ nuclei have been a perfect avenue avenue for determining the Cabibbo-Kobayashi-Maskawa matrix element $V_{ud}$, which imposes powerful constraints on physics beyond the Standard Model at low energies. For a long time, the precision of $V_{ud}$ has been limited by uncertainties in radiative corrections that arise from non-perturbative strong interaction physics at both the hadronic and nuclear levels. In this talk, I will describe some recent efforts to pin down these corrections by combining dispersive analysis with experimental data, lattice QCD, and nuclear many-body calculations.

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Chien-Yeah Seng. 2025-08-21. High-precision determination of radiative corrections to superallowed nuclear beta decays. https://arxiv.org/abs/2508.15203

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