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arXiv · 1412.8572

Probing the Top Quark Flavour-Changing Neutral Current at a Future Electron-Positron Collider

Hoda Hesari·Hamzeh Khanpour·Morteza Khatiri Yanehsari·Mojtaba Mohammadi Najafabadi
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Abstract

We present a study to examine the sensitivity of a future $e^{-} e^{+}$ collider to the anomalous top flavour-changing neutral current (FCNC) to the gluon. To separate signal from background a multivariate analysis is performed on top-quark pair and background events, where one top quark is considered to follow the dominant Standard Model (SM) decay, $t \rightarrow Wb$, and the other top decays through FCNC, $t\rightarrow qg$, where $q$ is a $u-$ or a $c-$quark. The analysis of fully-hadronic FCNC decay of the $t \bar{t}$ pair is also presented. The $95\%$ confidence level limits on the top-quark anomalous couplings are obtained for different values of the center-of-mass energies and integrated luminosities.

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Hoda Hesari, Hamzeh Khanpour, Morteza Khatiri Yanehsari, Mojtaba Mohammadi Najafabadi. 2014-12-30. Probing the Top Quark Flavour-Changing Neutral Current at a Future Electron-Positron Collider. https://doi.org/10.1155/2014%2F476490

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