Search for vector-like quarks in events with two oppositely charged leptons and jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV

Abstract

A search for the pair production of heavy vector-like partners T and B of the top and bottom quarks has been performed by the CMS experiment at the CERN LHC using proton-proton collisions at . The data sample was collected in 2016 and corresponds to an integrated luminosity of 35.9 production include those where one of the T quarks decays via TtZ and the other via TbW, tZ, or tH, where H is a Higgs boson. For the BB case, final states include those where one of the B quarks decays via BbZ and the other BtW, bZ, or bH. Events with two oppositely charged electrons or muons, consistent with coming from the decay of a Z boson, and jets are investigated. The number of observed events is consistent with standard model background estimations. Lower limits at 95% confidence level are placed on the masses of the T and B quarks for a range of branching fractions. Assuming 100% branching fractions for TtZ, and BbZ, T and B quark mass values below 1280 and 1130 respectively, are excluded.Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia Maria de Maeztu: MDM-2015-0509Programa Estatal de Fomento de la Investigacion Cientifica y Tecnica de Excelencia Maria de MaeztuFonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIA-Belgium)F.R.S.-FNRS (Belgium) under the Excellence of Science - EOS - be.h project: 30820817Chulalongkorn Academic into Its 2nd Century Project Advancement Project (Thailand)Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences (Hungary)Mobility Plus program of the Ministry of Science and Higher Education (Poland)FWO (Belgium) under the Excellence of Science - EOS - be.h project: 30820817F.R.S.-FNRS (Belgium) under the Excellence of Science - EOS - be.h project