Abstract
We provide a combined explanation of the increasingly tantalizing B-meson anomalies, both in \( {R}_{K^{\left(\ast \right)}} \) and \( {R}_{D^{\left(\ast \right)}} \), in the Pati-Salam model with minimal matter content. This well-known model, based on the gauge group SU(4)LC × SU(2)L × SU(2)R, naturally contains a variety of scalar leptoquarks with related and restricted couplings. In particular we show that the seesaw-motivated scalar leptoquark within the representation (\( \overline{\mathbf{10}} \),3,1) and its right-handed parity partner (\( \overline{\mathbf{10}} \),1,3) can solve both anomalies while making testable predictions for related observables such as B → Kνν and B → Kμτ. The solution of the \( {R}_{K^{\left(\ast \right)}} \) anomaly alone can be related to a type-II seesaw neutrino mass structure. Explaining also \( {R}_{D^{\left(\ast \right)}} \) requires the existence of a light right-handed neutrino, which constrains the UV structure of the model.
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Heeck, J., Teresi, D. Pati-Salam explanations of the B-meson anomalies. J. High Energ. Phys. 2018, 103 (2018). https://doi.org/10.1007/JHEP12(2018)103
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DOI: https://doi.org/10.1007/JHEP12(2018)103