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arXiv · 1101.1445

Top Quark Forward-Backward Asymmetry in the Large Invariant Mass Region

Kingman Cheung·Tzu-Chiang Yuan
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Abstract

The forward-backward asymmetry (FBA) in top-pair production that was observed in 2008 gets a boost in a recent CDF publication. Not only has the FBA further been confirmed, but also distributional preferences are shown. Strikingly, the FBA is the most sizable in the large $M_{t\bar t}$ invariant mass region and in the large rapidity difference $|\Delta y|$ region. Here we used our previously proposed $t$-channel exchanged $W'$ boson to explain the new observations. We show that a new particle exchanged in the $t$-channel generically gives rise to such observations. Furthermore, we show that the proposed $W'$ can be directly produced in association with a top quark at the Tevatron and the LHC. We perform a signal-background analysis and show that such a $W'$ is readily observed at the Tevatron with a 10 fb$^{-1}$ luminosity and at the LHC-7 with just a 100 pb$^{-1}$ luminosity.

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Kingman Cheung, Tzu-Chiang Yuan. 2011-01-07. Top Quark Forward-Backward Asymmetry in the Large Invariant Mass Region. https://doi.org/10.1103/physrevd.83.074006

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