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arXiv · 1112.5225

$W_H/Z_H$ production associated with a T-odd (anti)quark at the LHC in NLO QCD

Abstract

In the framework of the littlest Higgs model with T parity, we study the $W_H/Z_H$ production in association with a T-odd (anti)quark of the first two generations at the CERN Large Hadron Collider up to the QCD next-to-leading order. The kinematic distributions of final decay products and the theoretical dependence of the cross section on the factorization/renormalization scale are discussed. We apply three schemes in considering the QCD NLO contributions and find that the QCD NLO corrections by adopting the (II) and (III) subtraction schemes can keep the convergence of the perturbative QCD description and reduce the scale uncertainty of the leading order cross section. By using these two subtraction schemes, the QCD NLO corrections to the $W_H(Z_H) q_-$ production process enhance the leading order cross section with a K-factor in the range of $1.00 \sim 1.43$.

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BibTeXRIS

Zhang Ren-You, Yan Han, Ma Wen-Gan, Wang Shao-Ming, Guo Lei, Han Liang. 2011-12-23. $W_H/Z_H$ production associated with a T-odd (anti)quark at the LHC in NLO QCD. https://doi.org/10.1103/physrevd.85.015017

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