Measurement of the pp → ZZ production cross section and constraints on anomalous triple gauge couplings in four-lepton final states at vs=8TeV

Abstract

A measurement of the inclusive ZZ production cross section and constraints on anomalous triple gauge couplings in proton–proton collisions at vs=8 TeV are presented. The analysis is based on a data sample, corresponding to an integrated luminosity of 19.6fb-1, collected with the CMS experiment at the LHC. The measurements are performed in the leptonic decay modes ZZ ? lll’l’, where l =e, µand ll=e, µ, t. The measured total cross section s(pp ?ZZ) =7.7 ±0.5(stat)+0.5-0.4(syst)±0.4 (theo) ±0.2(lumi) pb, for both Z bosons produced in the mass range 60 <mZ<120GeV, is consistent with standard model predictions. Differential cross sections are measured and well described by the theoretical predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZand ZZ?couplings at the 95% confidence level: -0.004 <fZ4<0.004, -0.004 <fZ5<0.004, -0.005 <f?4<0.005, and -0.005 <f?5<0.005.