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arXiv · 1110.6163

Constraints on Randall-Sundrum model from top-antitop production at the LHC

Seyed Yaser Ayazi·Mojtaba Mohammadi Najafabadi
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Abstract

We study the top pair production cross section at the LHC in the context of Randall-Sundrum model including the Kaluza-Klein (KK) excited gravitons. It is shown that the recent measurement of the cross section of this process at the LHC restricts the parameter space in Randall-Sundrum (RS) model considerably. We show that the coupling parameter ($\frac{k}{\bar{M}_{pl}}$) is excluded by this measurement from 0.03 to 0.22 depending on the mass of first KK excited graviton ($m_1$). We also study the effect of KK excitations on the spin correlation of the top pairs. It is shown that the spin asymmetry in $t\bar{t}$ events is sensitive to the RS model parameters with a reasonable choice of model parameters.

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Seyed Yaser Ayazi, Mojtaba Mohammadi Najafabadi. 2011-12-07. Constraints on Randall-Sundrum model from top-antitop production at the LHC. https://doi.org/10.1007/jhep01(2012)111

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