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A search for narrow resonances in dielectron and dimuon invariant mass spectra has been performed using data obtained from proton–proton collisions at View the MathML source collected with the CMS detector. The integrated luminosity for the dielectron sample is 2.7 fb−1 and for the dimuon sample 2.9 fb−1. The sensitivity of the search is increased by combining these data with a previously analyzed set of data obtained at View the MathML source and corresponding to a luminosity of 20 fb−1. No evidence for non-standard-model physics is found, either in the 13 TeV data set alone, or in the combined data set. Upper limits on the product of production cross section and branching fraction have also been calculated in a model-independent manner to enable interpretation in models predicting a narrow dielectron or dimuon resonance structure. Limits are set on the masses of hypothetical particles that could appear in new-physics scenarios. For the View the MathML source particle, which arises in the sequential standard model, and for the superstring inspired View the MathML source particle, 95% confidence level lower mass limits for the combined data sets and combined channels are found to be 3.37 and 2.82 TeV, respectively. The corresponding limits for the lightest Kaluza–Klein graviton arising in the Randall–Sundrum model of extra dimensions with coupling parameters 0.01 and 0.10 are 1.46 and 3.11 TeV, respectively. These results significantly exceed the limits based on the 8 TeV LHC data. BMWF ; FWF ; FNRS ; FWO ; CNPq ; CAPES ; FAPERJ ; FAPESP ; MES ; CERN ; CAS ; MoST ; NSFC ; COLCIENCIAS ; MSES ; RPF ; MoER ; ERDF ; Academy of Finland ; MEC ; HIP ; CEA ; CNRS ; BMBF ; DFG ; HGF ; GSRT ; OTKA ; NKTH ; DAE ; DST ; IPM ; SFI ; INFN ; NRF ; WCU ; LAS ; CINVESTAV ; CONACYT ; UASLP-FAI ; MSI ; PAEC ; MSHE ; NSC ; FCT ; JINR ; MON ; RosAtom ; RAS ; RFBR ; MESTD ; SEIDI ; CPAN ; Swiss Funding Agencies ; NSC ; ThEPCenter ; IPST ; STAR ; NSTDA ; TUBITAK ; TAEK ; NASU ; STFC ; DOE ; NSF ; European Union ; the Leventis Foundation ; the A. P. Sloan Foundation ; the Alexander von Humboldt Foundation ; the Belgian Federal Science Policy Office ; the Fonds pour la Formation a` la Recherche dans l’Industrie et dans l’Agriculture (FRIA-Belgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWTBelgium); the Ministry of Education, Youth and Sports (MEYS) of Czech Republic; the Council of Science and Industrial Research, India; the Compagnia di San Paolo (Torino); the HOMING PLUS program of Foundation for Polish Science, cofinanced by EU, Regional Development Fund; and the Thalis and Aristeia programs cofinanced by EU-ESF and the Greek NSRF ; Qatar National Research Fund ; the Rachadapisek Sompot Fund for Postdoctoral Fellowship ; Chulalongkorn University ; the Welch Foundation. |
