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arXiv · 1705.08486

FCNC Decays of the Top Quark

Debjyoti Bardhan
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Abstract

If new physics (e.g. SUSY) does not show up as direct evidence at the LHC, it could still be observable in FCNC processes involving the $t$-quark. We take a close look at the process $t\to c + h/Z$ and show that its branching ratio in the Standard Model is subject to three mechanisms of suppression. To obtain an observable signal, one needs to evade all these mechanisms in a theory beyond the Standard Model. We show that a theory like the cMSSM cannot provide a big enough enhancement. However, in a framework like $R$-parity-violating SUSY, observable signals are a distinct possibility.

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Debjyoti Bardhan. 2017-05-23. FCNC Decays of the Top Quark. https://arxiv.org/abs/1705.08486

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