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arXiv · 1010.5700

Cross Section and Forward-Backward Asymmetry of $t\bar{t}$ Production in the Model with Four Color Symmetry

M. V. Martynov·A. D. Smirnov
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Abstract

The contributions to the cross section $\sigma_{t\bar{t}}$ and to the forward-backward asymmetry $A_{\rm FB}^{t \bar t}$ of $t\bar{t}$ production at the Tevatron from $Z'$-boson and scalar leptoquarks $S^{(\pm)}_a$ and scalar gluons $F_a$ predicted by the minimal model with four color quark-lepton symmetry are calculated. These contributions are shown to be small in tree approximation and can be significant with account of the 1-loop $gt\bar{t}$ effective vertex induced by the scalar doublets. The lower mass limit for scalar gluons $m_F \gtrsim 320\, GeV$ from the Tevatron data is obtained and it is shown that for $m_{F_1}\lesssim 990\,GeV$ the scalar gluon $F_1$ can be evident at LHC at the significance not less that $3\sigma$ (for $\sqrt{s}=14$ TeV, $L=10\,fb^{-1}$).

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M. V. Martynov, A. D. Smirnov. 2010-10-27. Cross Section and Forward-Backward Asymmetry of $t\bar{t}$ Production in the Model with Four Color Symmetry. https://arxiv.org/abs/1010.5700

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