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arXiv · 1405.0421

Measurement of the forward-backward asymmetry in top quark-antiquark production in ppbar collisions using the lepton+jets channel

D0 Collaboration
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Abstract

We present a measurement of the forward--backward asymmetry in top quark-antiquark production using the full Tevatron Run II dataset collected by the D0 experiment at Fermilab. The measurement is performed in lepton+jets final states using a new kinematic fitting algorithm for events with four or more jets and a new partial reconstruction algorithm for events with only three jets. Corrected for detector acceptance and resolution effects, the asymmetry is evaluated to be 10.6+-3.0 %. Results are consistent with the standard model predictions which range from 5.0% to 8.8%. We also present the dependence of the asymmetry on the invariant mass of the top quark--antiquark system and the difference in rapidities of top quark and antiquark.

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D0 Collaboration. 2014-05-02. Measurement of the forward-backward asymmetry in top quark-antiquark production in ppbar collisions using the lepton+jets channel. https://doi.org/10.1103/physrevd.90.072011

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