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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 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.

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Authors and Affiliations

  1. Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot, 76100, Israel

    Kfir Blum, Yonit Hochberg & Yosef Nir

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  1. Kfir Blum
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  2. Yonit Hochberg
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  3. Yosef Nir
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Correspondence to Yonit Hochberg.

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ArXiv ePrint: 1107.4350

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Blum, K., Hochberg, Y. & Nir, Y. Scalar-mediated \( t\bar{t} \) forward-backward asymmetry. J. High Energ. Phys. 2011, 124 (2011). https://doi.org/10.1007/JHEP10(2011)124

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