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arXiv · 1205.4721

Flipping t tbar asymmetries at the Tevatron and the LHC

Jure Drobnak·Jernej F. Kamenik·Jure Zupan
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Abstract

We show that the charge asymmetry in t tbar production at the LHC, A_C, and the forward-backward asymmetry at the Tevatron, A_FB, are in general not tightly correlated. They can even have opposite signs, if the underlying new physics (NP) model is general enough. We demonstrate this using two examples of NP: a light axigluon, and a vector that is a color octet and electroweak triplet. The small value of A_C measured at the LHC is thus shown not to exclude a NP interpretation of the anomalously large A_FB at the Tevatron. We identify two observables where significant NP effects are still expected at the Tevatron and the LHC, the b bbar production forward-backward asymmetry and spin polarizations of the pair-produced tops and anti-tops.

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Jure Drobnak, Jernej F. Kamenik, Jure Zupan. 2012-05-21. Flipping t tbar asymmetries at the Tevatron and the LHC. https://doi.org/10.1103/physrevd.86.054022

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