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

Physical review D: Particles and fields (Impact Factor: 4.86). 10/2011; 85(3). DOI: 10.1103/PhysRevD.85.034020
Source: arXiv


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.

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