On the statistical treatment of the Cabibbo angle anomaly

@article{Grossman2019OnTS,
  title={On the statistical treatment of the Cabibbo angle anomaly},
  author={Yuval Grossman and Emilie Passemar and Stefan Schacht},
  journal={Journal of High Energy Physics},
  year={2019},
  volume={2020},
  pages={1-13}
}
We point out that testing the equality of the Cabibbo angle as extracted from Γ( K → πlν ), the ratio Γ( K → lν )/Γ( π → lν ) and nuclear β decays is not identical to a test of first row unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix. The reason is that a CKM unitarity test involves only two parameters, while the degrees of freedom for the assessment of the goodness-of-fit of the universality of the Cabibbo angle entailed by the Standard Model (SM) is equal to the number of… 

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