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Résumé |
We examine various scenarios in which the Standard Model is extended by a light leptoquark
state to solve for one or both B-physics anomalies, namely RK, or RD(*). To do so, we
combine the constraints arising from low–energy observables and from direct searches at the
LHC, showing that none of the scalar leptoquarks of mass mLQ ~ 1 TeV can, by itself,
simultaneously accommodate both of the above mentioned anomalies. The only single
leptoquark scenario which can provide a viable solution for mLQ ~ 1 TeV is a vector
leptoquark, known as U1, which we re-examine in its minimal form, letting it couple only to
left-handed fermions. We discuss how the limits deduced from LHC direct searches are
complementary to the low–energy physics constraints. Focusing on lepton flavor violating b ->
sll modes, we show that improving the experimental upper bound on Br(B -> K mu tau) by two
orders of magnitude could compromise the minimal U1 model as a viable solution to the B-
physics anomalies. |
