Determination of |Vud| from nuclear mirror transitions

TL;DR

This paper demonstrates that the CKM matrix element |Vud| can be independently determined from nuclear mirror transitions, providing a competitive and consistent alternative to traditional methods like superallowed decays and neutron decay.

Contribution

The study introduces a new method to determine |Vud| using nuclear mirror transitions, offering an independent and precise measurement.

Findings

|Vud| = 0.9719 ± 0.0017 from mirror transitions

Result consistent with superallowed and neutron decay values

Potential for improved precision with future experiments

Abstract

The Vud element of the Cabibbo-Kobayashi-Maskawa quark mixing matrix has traditionally been determined from the analysis of data in nuclear superallowed 0+ to 0+ transitions, neutron decay and pion beta decay. We show here that this element can independently be determined from nuclear mirror transitions. The extracted value, |Vud| = 0.9719 +- 0.0017, is at 1.2 combined standard deviations from the value obtained in superallowed 0+ to 0+ transitions and has a similar precision than the value obtained from neutron decay experiments. We discuss some prospects to improve its precision through experiments in nuclear mirror transitions.