Search for narrow resonances in dilepton mass spectra in pp collisions at √s = 7 TeV

Authors

CMS Collaboration
Ekaterina Avdeeva, University of Nebraska-LincolnFollow
Kenneth A. Bloom, University of Nebraska-LincolnFollow
S. Bose, University of Nebraska-LincolnFollow
Jamila Butt, University of Nebraska-Lincoln
Daniel R. Claes, University of Nebraska-LincolnFollow
Aaron Dominguez, University of Nebraska-LincolnFollow
Michael Eads, University of Nebraska-LincolnFollow
P. Jindal, University of Nebraska-Lincoln
J. Keller, University of Nebraska-LincolnFollow
Ilya Kravchenko, University of Nebraska-LincolnFollow
J. Lazo-Flores, University of Nebraska-LincolnFollow
H. Malbouisson, University of Nebraska-Lincoln
Sudhir Malik, University of Nebraska-LincolnFollow
Gregory Snow, University of Nebraska-LincolnFollow

Document Type

Article

Date of this Version

2012

Citation

Physics Letters B 714 (2012) 158–179; http://dx.doi.org/10.1016/j.physletb.2012.06.051

Abstract

A search for narrow, high-mass resonances decaying to electron or muon pairs has been performed using pp collision data collected at √s = 7 TeV by the CMS experiment in 2011. The data sample corresponds to an integrated luminosity of approximately 5 fb⁻¹. The event yields observed in the signal regions are consistent with predictions of the standard model backgrounds, and upper limits on the cross section times branching fraction for a resonance decaying to dileptons are extracted from a shape analysis of the dilepton invariant mass distribution. The resulting mass limits at 95% confidence level are 2330 GeV for the Z' in the Sequential Standard Model, 2000 GeV for the superstring-inspired Z'_ψ resonance, 890 (540) GeV for the Stueckelberg extension Z'_St with the mass parameter є = 0.06 (0.04), and 2140 (1810) GeV for Kaluza–Klein gravitons with the coupling parameter k/M̅_Pl of 0.10 (0.05). These limits are the most stringent to date.