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arXiv · 1904.04121

Quark masses, CKM angles and Lepton Flavour Universality violation

Riccardo Barbieri·Robert Ziegler
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Abstract

A properly defined and suitably broken $U(2)$ flavour symmetry leads to successful quantitative relations between quark mass ratios and CKM angles. At the same time the intrinsic distinction introduced by $U(2)$ between the third and the first two families of quarks and leptons may support anomalies in charged and neutral current semi-leptonic $B$-decays of the kind tentatively observed in current flavour experiments. We show how this is possible by the exchange of the $(3,1)_{2/3}$ vector leptoquark in two $U(2)$-models with significantly different values of Lepton Flavour Universality violation, observable in foreseen experiments.

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Riccardo Barbieri, Robert Ziegler. 2019-07-11. Quark masses, CKM angles and Lepton Flavour Universality violation. https://doi.org/10.1007/jhep07(2019)023

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