Search for physics beyond the standard model in dilepton mass spectra in proton-proton collisions at sqrt(s) = 8 TeV

Understand

Dimuon and dielectron mass spectra, obtained from data resulting from proton-proton collisions at 8 TeV and recorded by the CMS experiment, are used to search for both narrow resonances and broad deviations from standard model predictions.

• The data correspond to an integrated luminosity of 20.6 (19.7) inverse femtobarns for the dimuon (dielectron) channel.
• No evidence for non-standard-model physics is observed and 95% confidence level limits are set on parameters from a number of new physics models.
• The narrow resonance analyses exclude a Sequential Standard Model Z'[SSM] resonance lighter than 2.90 TeV, a superstring-inspired Z'[psi] lighter than 2.57 TeV, and Randall-Sundrum Kaluza-Klein gravitons with masses below 2.73, 2.35, and 1.27 TeV for couplings of 0.10, 0.05, and 0.01, respectively.