Search for supersymmetric top quarks in the CMS Run 2 data set.

Abstract

Elementary particle physics is described very accurately by the Standard Model. With the discovery of the Higgs boson at CERN by ATLAS and CMS in 2012, the full set of fundamental particles in the Standard Model has been confirmed to exist by experimentation. The LHC and the CMS detector continue to probe physics at higher energies to determine if additional fundamental particles exist that are not present in the Standard Model. An analysis of the CMS Run 2 data set collected during the years 2016–2018 at center-of-mass energy 13 TeV corresponding to an integrated luminosity of 137.0 fb−1 is presented. This analysis searches for supersymmetric top quarks in the all-hadronic final state. The search targets multiple simplified SUSY models. Custom algorithms are used to identify top quarks and W bosons. The leading Standard Model background processes are t¯t, W(→ lν)+jets, Z(→ ν¯ν)+jets, QCD, and t¯tZ. A complete description of the Z(→ ν¯ν)+jets data-driven background prediction is given. The results are interpreted for several simplified SUSY models, and limits are placed on the masses of the supersymmetric top quark (up to 1.3 TeV), the gluino (up to 2.3 TeV), and the lightest supersymmetric particle (up to 1.4 TeV).