A Supersymmetric Top Quark Search Using a Top-Tagger at 8 TeV

A search for pairs of supersymmetric top quarks (stops) decaying to a top quark and a stable, weakly interacting, massive particle (neutralino) is presented. The search selects events containing multiple jets, with at least one identified as originating from a bottom quark, and large missing transverse momentum. The search employs a novel top-tagging algorithm which identifies a top quark candidate decaying into a bottom quark and two light flavor quarks. The analysis uses 19.4 fb-1 of proton-proton collision data collected at a center-of-mass energy of 8 TeV by the CMS detector at the Large Hadron Collider. The observed event yields are consistent with the SM expectations. Assuming each stop decays only into a top quark and a weakly interacting, neutral particle, stop production with stop masses less than 535 GeV are excluded at 95% confidence-level for neutralino masses less than 10 GeV. A summary of results for various analyses interpreted as simplified models are also presented. These results are based on data samples using 4.98fb-1 of integrated luminosity run at 7 TeV. A compilation of acceptance predictions and cross section upper limits for a range of simplified models and mass parameters are shown. The results provide exclusion limits for various beyond-the-standard-model processes which can be used to constrain other theoretical models, while providing comparisons between CMS search strategies.