Next-to-leading order QCD effect of $W'$ on top quark Forward-Backward Asymmetry

TL;DR

This paper calculates the next-to-leading order QCD corrections to top quark pair production via a $W'$ boson, showing increased forward-backward asymmetry at the Tevatron and potential for distinguishing new physics at the LHC.

Contribution

It provides the first complete NLO QCD correction calculations for $W'$-mediated top pair production, improving the understanding of new physics effects on asymmetries.

Findings

NLO corrections slightly affect total cross section

NLO increases forward-backward asymmetry by about 9% at high invariant mass

Total cross section and charge asymmetry can distinguish new physics at the LHC

Abstract

We present the calculations of the complete next-to-leading order (NLO) QCD corrections to the total cross section, invariant mass distribution and the forward-backward asymmetry ($\rm A_{FB}$) of top quark pair production mediated by $W'$ boson. Our results show that in the best fit point in the parameter space allowed by data at the Tevatron, the NLO corrections change the new physics contributions to the total cross section slightly, but increase the $\rm A_{FB}$ in the large invariant mass region by about 9%. Moreover, we evaluate the total cross section and charge asymmetry ($\rm{A}_{\rm{C}}$) of top pair production at the LHC, and find that both total cross section and $A_{\rm C}$ can be used to distinguish NP from SM with the integrated luminosity increasing.