Search for physics beyond the standard model in dilepton mass spectra in proton-proton collisions at √s = 8 TeV
Name
Khachatryan-2015-Search for physics b.pdf
Size
885.79 KB
Format
Adobe PDF
Checksum (MD5)
bb1d30c28b12f13f5c83b8ff8c0cc40f
Author(s)
Apyan, Aram
Barbieri, Richard Alexander
Busza, Wit
Cali, Ivan Amos
Di Matteo, Leonardo
Gomez-Ceballos, Guillelmo
Goncharov, Maxim
Gulhan, Doga Can
Klute, Markus
Lai, Yue Shi
Date Issued
April 2015
Journal
Journal of High Energy Physics
Publisher
Springer-Verlag
Citation
Khachatryan, V., A. M. Sirunyan, A. Tumasyan, W. Adam, T. Bergauer, M. Dragicevic, J. Erö, et al. “Search for Physics Beyond the Standard Model in Dilepton Mass Spectra in Proton-Proton Collisions at √s = 8 TeV.” J. High Energ. Phys. 2015, no. 4 (April 2015). © CERN, for the benefit of the CMS Collaboration
Version
Final published version
Abstract
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) fb[superscript −1] 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 [subscript SSM] ′ resonance lighter than 2.90 TeV, a superstring-inspired Z [subscript ψ] ′ 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. A notable feature is that the limits have been calculated in a model-independent way to enable straightforward reinterpretation in any model predicting a resonance structure. The observed events are also interpreted within the framework of two non-resonant analyses: one based on a large extra dimensions model and one based on a quark and lepton compositeness model with a left-left isoscalar contact interaction. Lower limits are established on M[subscript S], the scale characterizing the onset of quantum gravity, which range from 4.9 to 3.3 TeV, where the number of additional spatial dimensions varies from 3 to 7. Similarly, lower limits on Λ, the energy scale parameter for the contact interaction, are found to be 12.0 (15.2) TeV for destructive (constructive) interference in the dimuon channel and 13.5 (18.3) TeV in the dielectron channel.
MIT Department
Massachusetts Institute of Technology. Department of Physics
Massachusetts Institute of Technology. Laboratory for Nuclear Science
Massachusetts Institute of Technology. School of Science
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1007/jhep04(2015)025
