Abstract
We present a comprehensive reevaluation of the values in superallowed nuclear decays crucial for the precise determination of and low-energy tests of the electroweak standard model. It consists of the first, fully data-driven analysis of the nuclear decay form factor, that utilizes isospin relations to connect the nuclear charged weak distribution to the measurable charge distributions. This prescription supersedes previous shell-model estimations, and allows for a rigorous quantification of theory uncertainties in which is absent in the existing literature. Our new evaluation shows an overall downward shift of the central values of at the level of 0.01%.
- Received 11 October 2023
- Revised 14 February 2024
- Accepted 22 March 2024
DOI:https://doi.org/10.1103/PhysRevC.109.045501
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