Abstract
Flavor symmetries that explain masses and mixings of the standard model fermions dictate flavor patterns for the couplings of scalar and vector leptoquarks to the standard model fermions. A generic feature is that couplings to SU(2)-doublet leptons are suppressed at least by one spurion of the discrete non-abelian symmetry breaking, responsible for neutrino mixing, while couplings to charged lepton singlets can be order one. We obtain testable patterns including those that predominantly couple to a single lepton flavor, or two, or in a skewed way. They induce lepton non-universality, which we contrast to current anomalies in B-decays. We find maximal effects in R D and \( {R_D}_{{}^{\ast }} \) at the level of ∼10 percent and few percent, respectively, while leptoquark effects in \( {R_K}_{{}^{\left(\ast \right)}} \) can reach order few×10 percent. Predictions for charm and kaon decays and μ − e conversion are worked out.
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Hiller, G., Loose, D. & Schönwald, K. Leptoquark flavor patterns & B decay anomalies. J. High Energ. Phys. 2016, 27 (2016). https://doi.org/10.1007/JHEP12(2016)027
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DOI: https://doi.org/10.1007/JHEP12(2016)027