$W_H$-pair Production in the Littlest Higgs Model with T parity in next-to-leading order QCD at LHC

TL;DR

This paper calculates the production of $W_H$-pairs in the Littlest Higgs model with T parity at the LHC, including next-to-leading order QCD corrections, to improve prediction accuracy and analyze potential signals over background.

Contribution

It provides the first NLO QCD calculation of $W_H$-pair production in this model, reducing theoretical uncertainties and enhancing the leading order cross section predictions.

Findings

QCD NLO corrections reduce scale uncertainty.

K-factor ranges from 1.09 to 1.22 depending on parameters.

Signal can be distinguished from background with proper cuts.

Abstract

In the framework of the littlest Higgs model with $T$ parity, we study the $W_H$-pair production at the CERN Large Hadron Collider up to the QCD next-to-leading order (NLO). The kinematic distributions of final decay products and the theoretical dependence of the cross section on the factorization/renormalization scale are analyzed. We adopt the PROSPINO scheme in the QCD NLO calculations to avoid double counting and keep the convergence of the perturbative QCD description. Our numerical results show that the QCD NLO corrections significantly reduce the scale uncertainty, and enhance the leading order integrated cross section with a $K$-factor in the range of $1.10-1.22$ ($1.09-1.17$) with the symmetry breaking scale $f$ varying from $400 GeV$ ($400 GeV$) to $1.5 TeV$ ($1.0 TeV$) at the $14 TeV$ $(8 TeV)$ LHC. We find that it is possible to select the signal events of the $W_H$-pair production from the $pp\to W^+ W^- \to e^+ \mu^-\nu_{e}\bar{\nu}_{\mu}+X$ background with high ratio of signature over background by taking proper lower limits on transverse momenta, invariant mass of the final charged leptons and the missing transverse momentum.