Measurement of the ZZ production cross section and Z → ℓ+ℓ−ℓ′+ℓ′− branching fraction in pp collisions at √s=8TeV

Abstract

Four-lepton production in proton–proton collisions, ⁎ ⁎ , where or μ, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.6 fb−1. The ZZ production cross section, , is measured for events with two opposite-sign, same-flavor lepton pairs produced in the mass region . The Z boson branching fraction to four leptons is measured to be for the four-lepton invariant mass in the range and dilepton mass for all opposite-sign, same-flavor lepton pairs. The results are in agreement with standard model predictions.