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arXiv · 1809.07562

A chiral SU(4) explanation of the $b\to s$ anomalies

Shyam Balaji·Robert Foot·Michael A. Schmidt
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Abstract

We propose a variant of the Pati-Salam model, with gauge group $SU(4)_C\times SU(2)_L\times U(1)_{Y'}$, in which the chiral left-handed quarks and leptons are unified into a $\underline{4}$ of $SU(4)_C$, while the right-handed quarks and leptons have quite a distinct treatment. The $SU(4)_C$ leptoquark gauge bosons can explain the measured deviation of lepton flavour universality in the rare decays: $\bar B \to \bar K^{(*)}\bar\ell\ell, \ell=\mu,e$ (taken as a hint of new physics). The model satisfies the relevant experimental constraints and makes predictions for the important $B$ and $\tau$ decays. These predictions will be tested at the LHCb and Belle II experiments when increased statistics become available.

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Shyam Balaji, Robert Foot, Michael A. Schmidt. 2018-09-20. A chiral SU(4) explanation of the $b\to s$ anomalies. https://doi.org/10.1103/physrevd.99.015029

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