Search for third-generation scalar leptoquarks decaying to a top quark and a $\tau$ lepton at $\sqrt{s}=$ 13 TeV

Abstract

A search for pair production of heavy scalar leptoquarks (LQs), each decaying into a top quark and a $\tau$ lepton, is presented. The search considers final states with an electron or a muon, one or two $\tau$ leptons that decayed to hadrons, and additional jets. The data were collected in 2016 in proton-proton collisions at $\sqrt{s}=$ 13 TeV with the CMS detector at the LHC, and correspond to an integrated luminosity of 35.9 fb${}^{-1}$. No evidence for pair production of LQs is found. Assuming a branching fraction of unity for the decay LQ$\to$t$\tau$, upper limits on the production cross section are set as a function of LQ mass, excluding masses below 900 GeV at 95% confidence level. These results provide the most stringent limits to date on the production of scalar LQs that decay to a top quark and a $\tau$ lepton.

Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/B2G-16-028 (CMS Public Pages)