Measurement of the ZZ production cross section in proton-proton collisions at √s=8 TeV using the ZZ → ℓ⁻ℓ⁺ℓ^′−ℓ^′+ and ZZ→ ℓ⁻ℓ⁺νν¯ decay channels with the ATLAS detector

A measurement of the ZZ production cross section in the ℓ⁻ℓ⁺ℓ^{′ −}ℓ^{′ +} and ℓ⁻ℓ⁺νν¯ channels (ℓ = e, μ) in proton-proton collisions at s=8TeV at the Large Hadron Collider at CERN, using data corresponding to an integrated luminosity of 20.3 fb⁻¹ collected by the ATLAS experiment in 2012 is presented. The fiducial cross sections for ZZ → ℓ⁻ℓ⁺ℓ^{′ −}ℓ^{′ +} and ZZ→ ℓ⁻ℓ⁺νν¯ are measured in selected phase-space regions. The total cross section for ZZ events produced with both Z bosons in the mass range 66 to 116 GeV is measured from the combination of the two channels to be 7.3 ± 0.4(stat) ± 0.3(syst)_{− 0.1} ^{− 0.2}(lumi) pb, which is consistent with the Standard Model prediction of 6. 6_{− 0.6} ^{+ 0.7} pb. The differential cross sections in bins of various kinematic variables are presented. The differential event yield as a function of the transverse momentum of the leading Z boson is used to set limits on anomalous neutral triple gauge boson couplings in ZZ production.[Figure not available: see fulltext.]