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Updated: May 5, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Searches for new physics using the tt¯ invariant mass distribution in pp collisions at √s=8 TeV
S Chatrchyan1, V Khachatryan, A M Sirunyan
1Yerevan Physics Institute, Yerevan, Armenia.
Abstract:
Searches for anomalous top quark-antiquark production are presented, based on pp collisions at √s=8 TeV. The data, corresponding to an integrated luminosity of 19.7 fb(-1), were collected with the CMS detector at the LHC. The observed tt¯ invariant mass spectrum is found to be compatible with the standard model prediction. Limits on the production cross section times branching fraction probe, for the first time, a region of parameter space for certain models of new physics not yet constrained by precision measurements.
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