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arXiv · 0712.0151

Top-Quark FCNC Decay t->cgg in Topcolor-assisted Technicolor Model

Huan-Jun Zhang
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Abstract

The topcolor-assisted technicolor (TC2) model predicts several pseudo-scalars called top-pions and at loop level they can induce the FCNC top quark decay t->cgg which is extremely suppressed in the Standard Model (SM). We find that in the allowed parameter space the TC2 model can greatly enhance such a FCNC decay and push the branching ratio up to 10^{-3}, which is much larger than the predictions in the SM (10^{-9}) and in the minimal supersymmetric model (10^{-4}). We also compare the result with the two-body FCNC decay t-> cg and find that the branching ratio of t-> cgg is slightly larger than t-> cg. Such enhanced FCNC top quark decays may serve as a good probe of TC2 model at the future top quark factory.

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Huan-Jun Zhang. 2007-12-02. Top-Quark FCNC Decay t->cgg in Topcolor-assisted Technicolor Model. https://doi.org/10.1103/physrevd.77.057501

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