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FCNC Top Quark Decays in Extra Dimensions

G. A. Gonzalez-Sprinberg·R. Martinez·J. -Alexis Rodriguez
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Abstract

The flavor changing neutral top quark decay t -> c X is computed, where X is a neutral standard model particle, in a extended model with a single extra dimension. The cases for the photon, X= γ$, and a Standard Model Higgs boson, X = H, are analyzed in detail in a non-linear$R_ξgauge. We find that the branching ratios can be enhanced by the dynamics originated in the extra dimension. In the limit where 1/R >> ->, we have found Br(t -> c γ) \simeq 10^{-10} for 1/R = 0.5 TeV. For the decay t -> c H, we have found Br(t -> cH) \simeq 10^{-10} for a low Higgs mass value. The branching ratios go to zero when 1/R -> \infty.

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G. A. Gonzalez-Sprinberg, R. Martinez, J. -Alexis Rodriguez. 2007-10-17. FCNC Top Quark Decays in Extra Dimensions. https://doi.org/10.1140/epjc%2Fs10052-007-0344-1

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