Search for dark matter and unparticles produced in association with a Z boson in proton-proton collisions at sqrt(s) = 8 TeV

Abstract

A search for evidence of particle dark matter (DM) and unparticle production at the LHC has been performed using events containing two charged leptons, consistent with the decay of a Z boson, and large missing transverse momentum. This study is based on data collected with the CMS detector corresponding to an integrated luminosity of 19.7 inverse femtobarns of pp collisions at the LHC at a center-of-mass energy of 8 TeV. No significant excess of events is observed above the number expected from the standard model contributions. The results are interpreted in terms of 90% confidence level limits on the DM-nucleon scattering cross section, as a function of the DM particle mass, for both spin-dependent and spin-independent scenarios. Limits are set on the effective cutoff scale Lambda, and on the annihilation rate for DM particles, assuming that their branching fraction to quarks is 100%. Additionally, the most stringent 95% confidence level limits to date on the unparticle model parameters are obtained.

Corrected the CERN-PH-EP number on the preprint. Figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/EXO-12-054/index.html

References in corpus (37)

• PYTHIA 6.4 Physics and Manual
• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Parton distributions for the LHC
• Matching NLO QCD computations with Parton Shower simulations: the POWHEG method
• A direct empirical proof of the existence of dark matter
• New parton distributions for collider physics
• Event generation with SHERPA 1.1
• Implications of CTEQ global analysis for collider observables
• Pileup subtraction using jet areas
• Single-top Wt-channel production matched with parton showers using the POWHEG method
• Unparticle Physics
• MCFM for the Tevatron and the LHC
• Performance of CMS muon reconstruction in pp collision events at sqrt(s) = 7 TeV
• Constraints on Dark Matter from Colliders
• Performance of electron reconstruction and selection with the CMS detector in proton-proton collisions at sqrt(s) = 8 TeV
• Search for Low-Mass WIMPs with SuperCDMS
• The PDF4LHC Working Group Interim Recommendations
• The Tevatron at the Frontier of Dark Matter Direct Detection
• Another Odd Thing About Unparticle Physics
• Interleaved Parton Showers and Tuning Prospects
• First dark matter search results from a 4-kg CF${}_3$I bubble chamber operated in a deep underground site
• The PDF4LHC Working Group Interim Report
• Dark Matter Search Results from the PICO-2L C${}_3$F${}_8$ Bubble Chamber
• Constraints on Low-Mass WIMP Interactions on 19F from PICASSO
• Collider signals in unparticle physics
• Search for invisible decays of Higgs bosons in the vector boson fusion and associated ZH production modes
• Collider Phenomenology of Unparticle Physics
• On the Validity of the Effective Field Theory for Dark Matter Searches at the LHC Part III: Analysis for the $t$-channel
• Search for dark matter in events with a Z boson and missing transverse momentum in pp collisions at $\sqrt{s}$=8 TeV with the ATLAS detector
• Study of ${\chi }_{cJ}$ decaying into $\varphi$ $K^{\ast }(892)$ $\bar{K}$
• Search for dark matter in events with heavy quarks and missing transverse momentum in $pp$ collisions with the ATLAS detector
• Search for new particles in events with one lepton and missing transverse momentum in $pp$ collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
• Inflation in scale-invariant theories of gravity
• Search for monotop signatures in proton-proton collisions at sqrt(s) = 8 TeV
• Search for invisible particles produced in association with single-top-quarks in proton-proton collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
• Simulation of Z plus Graviton/Unparticle Production at the LHC
• Bounds from LEP on unparticle interactions with electroweak bosons

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• Mono-X Versus Direct Searches: Simplified Models for Dark Matter at the LHC
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• Impact of cosmological and astrophysical constraints on dark matter simplified models
• Vector Boson Fusion Searches for Dark Matter at the LHC
• Unitarity Bounds on Effective Field Theories at the LHC
• Interpretation of neutral charm mesons near threshold as unparticles
• Impact of Jet Veto Resummation on Slepton Searches
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• Indirect searches of Galactic diffuse dark matter in INO-MagICAL detector
• The influence of the scalar unparticle on the W-pair production at ILC in the Randall Sundrum model
• Investigation of the scalar unparticle and anomalous couplings at muon colliders in final states with multiple photons in the Randall- Sundrum model
• Constraining unparticle physics from $CP$ violation in Cabibbo-favored decays of D mesons
• LHC-friendly freeze-in dark matter via Higgs portal
• Search for the production of dark fermion candidates in association with heavy neutral gauge boson decaying to dimuon in proton-proton collisions at $\sqrt{s}=8$ TeV using the CMS open data
• Search for dark matter production in association with the Z${}^{\prime }$ boson at the LHC in pp collisions at $\sqrt{s}$ = 8 TeV using Monte Carlo simulations