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arXiv · 1204.2885

A clean signal for a top-like isosinglet fermion at the Large Hadron Collider

Aarti Girdhar·Biswarup Mukhopadhyaya
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Abstract

We predict a clean signal at the Large Hadron Collider ($\sqrt s)$=14 TeV for a scenario where there is a top-like, charge +2/3 vectorlike isosinglet fermion. Such a quark, via mixing with the standard model top, can undergo decays via both flavour-changing Z-boson coupling and flavour-changing Yukawa interactions. We concentrate on the latter channel, and study the situation where, following its pair-production, the heavy quark pair gives rise to two tops and two Higgs boson. We show that the case where each Higgs decays in the $b\bar{b}$ channel, there can be a rather distinct and background-free signal that can unveil the existence of the vectorlike isosinglet quark of this kind.

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Aarti Girdhar, Biswarup Mukhopadhyaya. 2012-04-13. A clean signal for a top-like isosinglet fermion at the Large Hadron Collider. https://doi.org/10.1007/s12043-013-0618-0

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