Search for supersymmetric partners of the top quark with the CMS detector and novel top quark tagging algorithms.

Abstract

The standard model of particle physics has been highly successful in explaining observed interactions of subatomic particles. The model was largely vindicated with the announced observation of the Higgs boson by the ATLAS and CMS experiments at the LHC. The astronomical observation of dark matter, among other reasons, motivates us to look for particles not part of the standard model. One extension of the model posits an additional symmetry which pairs every particle with a supersymmetric partner; fermions paired to bosons, and bosons paired with fermions. Using data collected with the CMS detector at a center of mass energy of 13 TeV during 2016, we have looked for evidence that the superpartner of the top quark was produced then decayed into an undetected particle and a top quark that decayed to hadronic jets. No statistically significant deviation from standard model expectations is observed. Limits are placed on the production cross section in the context of a simplified supersymmetric model. The search for the production of supersymmetric particles will continue with larger datasets and more sophisticated analyses. An improved top quark tagging algorithm with enhanced sensitivity to top quarks that decay into three hadronic jets is presented.