Revisiting the large extra dimension effects on $W$-pair production at the LHC in NLO QCD

TL;DR

This paper studies how large extra dimensions influence W-pair production at the LHC, incorporating NLO QCD corrections to improve the accuracy of predictions and explore the parameter space where LED effects are observable.

Contribution

It provides a detailed analysis of LED effects on W-pair production at NLO QCD, including the impact of kinematic cuts and scale uncertainties, which was not thoroughly explored before.

Findings

NLO QCD corrections significantly affect observables.

Optimal kinematic cuts enhance LED effect detection.

Scale uncertainties remain large at NLO, with no improvement over LO.

Abstract

In the framework of the large extra dimensions (LED) model, we investigate the effects induced by the Kaluza-Klein (KK) gravitons up to the QCD next-to-leading order (NLO) on the $W$-pair production followed by a subsequential $W$-decay at the CERN LHC. We depict the regions in the $\mathcal{L}-M_{S}$ parameter space where the LED effect can and cannot be observed from the analyses of the $pp \to W^+W^- + X$ and $pp \to W^+W^- \to W^{\pm}l^{\mp}\stackrel{(-)}{\nu} + X$ processes. We find that the ability of probing the LED effects can be improved by taking the cutoffs for the invariant mass of $W$-pair and the transverse momentum of the final lepton. Our results demonstrate that the NLO QCD corrections to observables are significant, and do not show any improvement for the renormalization/factorization scale uncertainty on the QCD NLO corrected cross section, because the LO result underestimates the scale dependence.