Vector Leptoquarks Beyond Tree Level

TL;DR

This paper investigates the effects of one-loop corrections in models with massive vector leptoquarks from an $SU(4)$ gauge symmetry, highlighting significant implications for phenomenology and experimental searches.

Contribution

It provides a next-to-leading order analysis of low- and high-energy observables in vector leptoquark models, emphasizing the importance of loop corrections for large gauge couplings.

Findings

One-loop corrections significantly enhance low-energy contributions.

Large gauge couplings lead to sizeable quantum effects.

Results impact current and future leptoquark searches.

Abstract

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 $g_4$. For large values of $g_4$, 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.