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 fb(-1) 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. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.
Search for a narrow, spin-2 resonance decaying to a pair of Z bosons in the q(q)over-barl(+)l(-) final state
LIGABUE, FRANCO;ROLANDI, LUIGI;
2013
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 fb(-1) 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. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.