Search for Resonances in the Dilepton Mass Distribution in pp Collisions at

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) → `+` − relative to Z → `+` − are presented. These limits exclude at 95 % confidence level a Z ′ with standard-model-like couplings below 1140 GeV, the superstring-inspired Z′ψ below 887 GeV, and, for values of the coupling parameter k/MPl of 0.05 (0.1), Kaluza–Klein gravitons below 855 (1079) GeV. Submitted to the Journal of High Energy Physics ∗See Appendix A for the list of collaboration members a