# Scalar-mediated \( t\bar{t} \) forward-backward asymmetry

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## Abstract

A large forward-backward asymmetry in \( t\bar{t} \) production, for largeinvariant 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, all colored representations are inconsistent by more than 2*σ* with at least one other top-related measurement. In contrast, the *t*-channel exchange of a color-singlet weak-doublet scalar is consistent with the differential and with the 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.

## Keywords

Phenomenological Models## References

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