Journal of High Energy Physics

, 2011:124 | Cite as

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

Article

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 2σ 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 

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Copyright information

© SISSA, Trieste, Italy 2011

Authors and Affiliations

  1. 1.Department of Particle Physics and AstrophysicsWeizmann Institute of ScienceRehovotIsrael

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