Search for Supersymmetry in pp collisions at 8 TeV in events with a single lepton, multiple jets and b-tags

Results are reported from a search for new physics in pp collisions at a center-of-mass energy $\sqrt{s}=8$ TeV, focusing on the signature with a single isolated lepton (e or $\mu$), multiple energetic jets, some of which are b-tagged, and large total event transverse energy. The data sample comprises an integrated luminosity of 19.4~fb$^{-1},$ recorded by the CMS experiment at the Large Hadron Collider. The search is motivated by models of new physics, including supersymmetry, that involve strong production processes and cascade decays producing many jets and missing momentum from unobserved, weakly interacting particles. The event yields observed across several kinematic regions are consistent with standard model backgrounds predicted using a mix of simulated event samples and control samples in the data. The results are interpreted using a benchmark model with pair production of gluinos, each of which decays to a pair of top quarks and a neutralino. In this model, gluinos with a mass smaller than about $1.3$ TeV are excluded for neutralino masses below about $0.5$ TeV.