Model for the singlet-triplet leptoquarks

The deviations of B-meson decays measured in R-D(*)(tau l) and R-K(*)(mu e) can be explained by the presence of two scalar leptoquarks, a singlet S-1 and a triplet S-3, mostly coupled to the third generation. We consider a theory of resonances, as an effective description of a strongly interacting theory, that generates the leptoquarks and the Higgs as Nambu-Goldstone bosons, with the rest of the resonances at a scale of order 10-30 TeV. We assume anarchic partial compositeness for the flavor of the SM fermions. Under this hypothesis, we study whether it is possible to reproduce the deviations in the B decays without being in conflict with flavor and electroweak bounds. We find a tension between R-D(*)(tau l) and some flavor observables, dominated by flavor violating tau decays and Delta m(Bs), that require a tuning of order 10%-25%. We also compute the potential of the scalars showing that leptoquarks with masses O(2-3) TeV can be naturally expected in the model. We discuss briefly the phenomenology of the other resonances.

Automated summary

The study explores the deviations in B-meson decays by considering the presence of two scalar leptoquarks S-1 and S-3, with a tension between R-D(*)(tau l) and some flavor observables. The potential of the scalars suggests that leptoquarks with masses O(2-3) TeV can be naturally expected in the model, and briefly discusses the phenomenology of other resonances.