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arXiv · 1107.4350

Scalar-mediated $t\bar t$ forward-backward asymmetry

Kfir Blum·Yonit Hochberg·Yosef Nir
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Abstract

A large forward-backward asymmetry in $t\bar t$ production, for large invariant mass of the $t\bar t$ system, has been recently observed by the CDF collaboration. Among the scalar mediated mechanisms that can explain such a large asymmetry, only the t-channel exchange of a color-singlet weak-doublet scalar is consistent with both differential and integrated $t\bar t$ cross section measurements. Constraints from flavor changing processes dictate a very specific structure for the Yukawa couplings of such a new scalar. No sizable deviation in the differential or integrated $t\bar t$ production cross section is expected at the LHC.

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Kfir Blum, Yonit Hochberg, Yosef Nir. 2011-08-03. Scalar-mediated $t\bar t$ forward-backward asymmetry. https://doi.org/10.1007/jhep10(2011)124

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