# 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} }

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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