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arXiv · 1107.2606

The electroweak contribution to the top quark forward-backward asymmetry at the Tevatron

Wolfgang Hollik·Davide Pagani
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Abstract

The electroweak contributions to the forward-backward asymmetry in the production of top-quark pairs at the Tevatron are evaluated at O(alpha^2) and O(alpha*alphas^2). We perform a detailed analysis of all partonic channels that produce an asymmetry and combine them with the QCD contributions. They provide a non-negligible fraction of the QCD-induced asymmetry with the same overall sign, thus enlarging the Standard Model prediction and diminishing the observed deviation. For the observed mass-dependent forward-backward asymmetry a 3-sigma deviation still remains at an invariant-mass cut of M_(t-tbar) > 450 GeV.

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Wolfgang Hollik, Davide Pagani. 2011-07-13. The electroweak contribution to the top quark forward-backward asymmetry at the Tevatron. https://doi.org/10.1103/physrevd.84.093003

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