Suche nach skalaren Leptoquarks der dritten Generation im Zerfallskanal LQ3 → t τ am LHC

In this study a search for third generation scalar leptoquarks using data collected with the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC) is presented. Leptoquarks are hypothetical particles which couple to leptons and bosons and therefore establish a connection between the lepton- and the quark-sector. The pair production of leptoquarks is studied at the LHC in the decay channel LQ3 → t τ. In the final state at least one hadronically decaying tau lepton, at least one electron, several jets and missing transverse energy are expected. For this analysis the whole CMS dataset from 2012, with a center-of-mass energy of √ s = 8 TeV according to an integrated luminosity of 19.7 fb−1 is analysed. No excess over the standard model expectation is observed and limits on the production cross section σ(pp → LQ3 LQ3, LQ3 → t τ) at 95% Confidence Level (CL) are calculated. The results obtained in this analysis are combined with the results from two other studies in the muon channel. In the combination scalar leptoquarks of the third generation can be excluded up to a mass of 670 GeV/c 2 .