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arXiv · 1209.3807

Search for a narrow, spin-2 resonance decaying to a pair of Z bosons in the q q-bar l+l- final state

CMS Collaboration
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Abstract

Results are presented from a search for a narrow, spin-2 resonance decaying into a pair of Z bosons, with one Z-boson decaying into leptons (e+e- or mu+mu-) and the other into jets. An example of such a resonance is the Kaluza--Klein graviton, G[KK], predicted in Randall--Sundrum models. The analysis is based on a 4.9 inverse femtobarn sample of proton-proton collisions at a center-of-mass energy of 7 TeV, collected with the CMS detector at the LHC. Kinematic and topological properties including decay angular distributions are used to discriminate between signal and background. No evidence for a resonance is observed, and upper limits on the production cross sections times branching fractions are set. In two models that predict Z-boson spin correlations in graviton decays, graviton masses are excluded lower than a value which varies between 610 and 945 GeV, depending on the model and the strength of the graviton couplings.

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CMS Collaboration. 2013-03-13. Search for a narrow, spin-2 resonance decaying to a pair of Z bosons in the q q-bar l+l- final state. https://doi.org/10.1016/j.physletb.2012.11.063

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