# Cabibbo anomaly versus electroweak precision tests: An exploration of extensions of the standard model

@article{Kirk2021CabibboAV,
title={Cabibbo anomaly versus electroweak precision tests: An exploration of extensions of the standard model},
author={Matthew Kirk},
journal={Physical Review D},
year={2021},
volume={103},
pages={035004}
}
• M. Kirk
• Published 7 August 2020
• Physics
• Physical Review D
There is a newly emerging tension between determinations of ${V}_{us}$ from different sources (known as the Cabibbo anomaly), clearly demonstrated by the new $R({V}_{us})$ observable which is highly sensitive to lepton flavor universality violating effects. We explore this observable from the perspective of the Standard Model Effective Field Theory and show there is a discrepancy between $R({V}_{us})$ and existing electroweak precision observables (EWPO) in a simple single operator dominated…

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