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arXiv · 1011.5508

Light Stop Searches at the LHC in Events with two b-Jets and Missing Energy

S. Bornhauser·M. Drees·S. Grab·J. S. Kim
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Abstract

We propose a new method to discover light top squarks (stops) in the co-annihilation region at the Large Hadron Collider (LHC). The bino-like neutralino is the lightest supersymmetric particle (LSP) and the lighter stop is the next-to-LSP. Such scenarios can be consistent with electroweak baryogenesis and also with dark matter constraints. We consider the production of two stops in association with two b-quarks, including pure QCD as well as mixed electroweak-QCD contributions. The stops decay into a charm quark and the LSP. For a higgsino-like light chargino the electroweak contributions can exceed the pure QCD prediction. We show the size of the electroweak contributions as a function of the stop mass and present the LHC discovery reach in the stop-neutralino mass plane.

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S. Bornhauser, M. Drees, S. Grab, J. S. Kim. 2010-11-24. Light Stop Searches at the LHC in Events with two b-Jets and Missing Energy. https://doi.org/10.1103/physrevd.83.035008

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