# 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…

## 33 Citations

### Global Fit to Modified Neutrino Couplings and the Cabibbo-Angle Anomaly.

- PhysicsPhysical review letters
- 2020

A model-independent global analysis in a Bayesian approach is performed and it is found that the tension in the Cabibbo angle is significantly reduced, while the agreement with other data is also mostly improved.

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

- Physics
- 2021

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…

### β Decays as Sensitive Probes of Lepton Flavor Universality.

- PhysicsPhysical review letters
- 2020

It is found that the ratio of V_{US} from kaon decays over V_{us} from β decays (assuming CKM unitarity) is extremely sensitive to LFU violation (LFUV) in W-μ-ν couplings thanks to a CKM enhancement by (V_{ud}/V_{us})^{2}∼20.

### B anomalies under the lens of electroweak precision

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Abstract
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- PhysicsJournal of High Energy Physics
- 2021

<jats:title>A<jats:sc>bstract</jats:sc>
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### Minimal Explanation of Flavor Anomalies: B-Meson Decays, Muon Magnetic Moment, and the Cabibbo Angle.

- PhysicsPhysical review letters
- 2021

This framework provides the most minimal explanation to the above-mentioned anomalies, while being consistent with all other phenomenological constraints.

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- Physics
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In this work we investigate the implication of low-energy precision measurements on the quark-lepton charged currents in general neutrino interactions with sterile neutrinos in effective field…

### New method for calculating electromagnetic effects in semileptonic beta-decays of mesons

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- 2020

We construct several classes of hadronic matrix elements and relate them to the low-energy constants in Chiral Perturbation Theory that describe the electromagnetic effects in the semileptonic beta…

### Muon g − 2 and CKM unitarity in extra lepton models

- Physics
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We investigate the impact of extra leptons on observed tensions in the muon $g-2$ and the first-row CKM unitarity. By introducing a new SU(2)$_L$ doublet lepton and a SU(2)$_L$ triplet lepton, we…

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