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arXiv · 1711.03945

The top-quark charge asymmetry at the LHC and Tevatron through NNLO QCD and NLO EW

Abstract

We provide the most up-to-date predictions for the top-quark charge asymmetry A_C at the LHC with a centre-of-mass energy of 8 TeV. Our result is accurate at the NNLO level in the strong interactions and at the complete-NLO level in both the strong and electroweak interactions. We present results for the inclusive A_C, several differential asymmetries as well as the P_{T,tt} and M_{tt} cumulative asymmetries. Similarly to the Tevatron forward-backward asymmetry A_FB, both NNLO QCD and NLO EW corrections to A_C are found to be significant. The inclusion of higher-order corrections reduces the residual scale dependence in the predicted A_C. The pattern of higher-order corrections indicates good perturbative control over these observables. We conclude that at present there is nearly uniform agreement between Standard Model predictions and LHC measurements across all A_C-related observables. All previously published differential A_FB predictions at the Tevatron are updated to the same accuracy.

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Michal Czakon, David Heymes, Alexander Mitov, Davide Pagani, Ioannis Tsinikos, Marco Zaro. 2017-11-10. The top-quark charge asymmetry at the LHC and Tevatron through NNLO QCD and NLO EW. https://doi.org/10.1103/physrevd.98.014003

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