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arXiv · 2201.09949

Leptophilic New Physics and the Cabibbo Angle Anomaly

Fiona Kirk
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Abstract

The Cabibbo Angle Anomaly, an apparent deficit in first-row CKM unitarity, can be addressed by leptophilic Standard Model extensions that generate new contributions to the Fermi constant and affect the determination of the CKM element $V_{ud}$. We focus on simplified models with this property, including the Standard Model extended by vectorlike leptons, by the singly charged scalar singlet, or by a leptophilic $Z'$ boson.

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Fiona Kirk. 2022-01-24. Leptophilic New Physics and the Cabibbo Angle Anomaly. https://arxiv.org/abs/2201.09949

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