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Search for resonances in the dilepton mass distribution in pp collisions at sqrt(s)=7 TeV

A search for narrow resonances at high mass in the dimuon and dielectron channels has been performed by the CMS experiment at the CERN LHC, using pp collision data recorded at s=7 TeV. The event samples correspond to integrated luminosities of 40 pb−1 in the dimuon channel and 35 pb−1 in the dielectron channel. Heavy dilepton resonances are predicted in theoretical models with extra gauge bosons (Z′) or as Kaluza-Klein graviton excitations (GKK) in the Randall-Sundrum model. Upper limits on the inclusive cross section of Z′(GKK) → ℓ + ℓ − relative to Z → ℓ + ℓ − are presented. These limits exclude at 95% confidence level a Z′ with standard-model-like couplings below 1140GeV, the superstring-inspired Z ψ ′ below 887 GeV, and, for values of the coupling parameter kMPl of 0.05 (0.1), Kaluza-Klein gravitons below 855 (1079) GeV.

LHC; CMS; Beyond standard model; resonance search

The CMS collaboration