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arXiv · 1106.6051

The top-pair forward-backward asymmetry beyond NLO

Valentin Ahrens·Andrea Ferroglia·Matthias Neubert·Ben D. Pecjak·Li Lin Yang
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Abstract

We make use of recent results in effective theory and higher-order perturbative calculations to improve the theoretical predictions of the QCD contribution to the top-quark pair production forward-backward asymmetry at the Tevatron. In particular, we supplement the fixed-order NLO calculation with higher-order corrections from soft gluon resummation at NNLL accuracy performed in two different kinematic schemes, which allows us to make improved predictions for the asymmetry in the $p\bar p$ and $t\bar t$ rest frames as a function of the rapidity and invariant mass of the $t\bar t$ pair. Furthermore, we provide binned results which can be compared with the recent measurements of the forward-backward asymmetry in events with a large pair invariant mass or rapidity difference. Finally, we calculate at NLO+NNLL order the top-quark charge asymmetry at the LHC as a function of a lower rapidity cut-off for the top and antitop quarks.

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Valentin Ahrens, Andrea Ferroglia, Matthias Neubert, Ben D. Pecjak, Li Lin Yang. 2011-06-29. The top-pair forward-backward asymmetry beyond NLO. https://doi.org/10.1103/physrevd.84.074004

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