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

  title={Cabibbo anomaly versus electroweak precision tests: An exploration of extensions of the standard model},
  author={Matthew Kirk},
  journal={Physical Review D},
  • 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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