Lepton-Quark Fusion at Hadron Colliders, precisely

TL;DR

This paper calculates the first higher-order QCD and QED corrections to resonant leptoquark production at the LHC, enhancing precision in understanding leptoquark signals and flavor interactions.

Contribution

It provides the first NLO QCD and QED corrections for leptoquark production via lepton-quark fusion at hadron colliders, including detailed K-factors and uncertainty analysis.

Findings

NLO corrections are similar in size but opposite in sign.

Quantified theoretical uncertainties from scale variations and PDFs.

Discussed methods to distinguish leptoquark flavor structures.

Abstract

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.