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

TL;DR

This paper discusses recent efforts to precisely calculate radiative corrections in superallowed nuclear beta decays, which are crucial for accurately determining the CKM matrix element V_{ud} and testing the Standard Model.

Contribution

It introduces a combined approach using dispersive analysis, experimental data, lattice QCD, and nuclear many-body calculations to improve the accuracy of radiative correction estimates.

Findings

Enhanced precision in radiative correction calculations.

Improved constraints on the CKM matrix element V_{ud}.

Reduced uncertainties in tests of the Standard Model.

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.