Models with massive vector leptoquarks, resulting from an SU (4) gauge symmetry spontaneously broken at the TeV scale, are of great phenomenological interest given the current "anomalies" in semileptonic B decays. We analyze the relations between low-and high-energy observables in such class of models to next-to-leading order accuracy in the SU (4) gauge coupling g4. For large values of g4, motivated by recent B-physics data, one-loop corrections are sizeable. The main effect is an enhanced contribution at low-energy, at fixed on-shell couplings. This result has important implications for current and future high-energy searches of vector leptoquark models.

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When a TeV-scale leptoquark has a sizeable Yukawa coupling, its dominant production mechanism at hadron colliders is the partonic-level lepton-quark fusion. Even though the parton distribution functions for leptons inside the proton are minuscule, they get compensated by the resonant enhancement. We present the first computation of higher order radiative corrections to the resonant leptoquark production cross section at the Large Hadron Collider (LHC). Next-to-leading (NLO) QCD and QED corrections are similar in size but come with the opposite sign. We compute NLO K-factors for a wide range of scalar leptoquark masses, as well as, all possible combinations of quark and lepton flavors and leptoquark charges. Theoretical uncertainties due to the renormalisation and factorisation scale variations and the limited knowledge of parton distribution functions are quantified. We finally discuss how to disentangle the flavor structure of leptoquark interactions by exploiting the interplay between different production channels.

We clarify open issues in relating low-and high-energy observables, at next-to-leading order accuracy, in models with a massive leptoquark embedded in a flavor nonuniversal SUð4Þ × SUð3Þ × SUð2Þ × Uð1Þ gauge group. Extending previous work on this subject, we present a complete analysis of the Oðα s Þ corrections to the matching conditions of semileptonic operators at the high scale. These corrections are not negligible, but they do not exceed the 10% level and are subleading compared to the Oðα 4 Þ corrections proportional to the leading leptoquark coupling, which is expected to be much larger than the QCD coupling in the parameter space region of phenomenological interest. We further analyze the impact of radial modes, both at Oðα 4 Þ and at Oðα s Þ accuracies, highlighting their role in the renormalization of the theory.

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