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arXiv · 0909.3977

A Strong Sector at the LHC: Top Partners in Same-Sign Dileptons

Abstract

Heavy partners of the top quark are a common prediction of many models in which a new strongly-coupled sector is responsible for the breaking of the EW symmetry. In this paper we investigate their experimental signature at the LHC, focusing on the particularly clean channel of same-sign dileptons. We show that, thank to a strong interaction with the top quark which allows them to be singly produced at a sizable rate, the top partners will be discovered at the LHC if their mass is below 1.5 TeV, higher masses being possible in particularly favorable (but plausible) situations. Being the partners expected to be lighter in both the Higgsless and Composite-Higgs scenarios, the one of same-sign dileptons is found to be a very promising channel in which these models could be tested. We also discuss several experimental signatures which would allow, after the discovery of the excess, to uniquely attribute it to the top partners production and to measure the relevant physical parameters, i.e. the top partners masses and couplings. We believe that our results constitute a valid starting point for a more detailed experimental study.

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Jan Mrazek, Andrea Wulzer. 2009-09-22. A Strong Sector at the LHC: Top Partners in Same-Sign Dileptons. https://doi.org/10.1103/physrevd.81.075006

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