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arXiv · 1703.05007

Sensitivity of CLIC at 380 GeV to the top FCNC decay $t\rightarrow cH$

Aleksander Filip Żarnecki
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Abstract

In the Standard Model (SM), flavour changing neutral current (FCNC) top decays, possible at loop level only, are very strongly suppressed. Observation of any such decay would be a direct signature of physics beyond the SM. Large enhancements are possible in many "new physics" scenarios and the largest enhancement is in most cases expected for the $t\rightarrow cH$ decay. A full study for CLIC was based on the WHIZARD simulation of FCNC top decays within the 2HDM(III) model. Beam polarization and beam-induced background were taken into account. Top pair production events with the FCNC decay $t\rightarrow cH$ can be identified based on kinematic constrains and flavour tagging information. Due to a large overlap in the kinematic space with standard top pair events, the final signal selection-efficiency is small, at the 10% level. Expected limits on $BR(t\rightarrow cH)\times BR(H\rightarrow b\bar{b})$ are compared with earlier results based on parton level simulation.

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Aleksander Filip Żarnecki. 2017-03-15. Sensitivity of CLIC at 380 GeV to the top FCNC decay $t\rightarrow cH$. https://doi.org/10.1088/1742-6596/873/1/012049

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