Measurement of the cross section for electroweak production of Zγ in association with two jets and constraints on anomalous quartic gauge couplings in proton–proton collisions at s=8 TeV

A measurement is presented of the cross section for the electroweak production of a Z boson and a photon in association with two jets in proton–proton collisions at √s = 8 TeV. The Z bosons are identified through their decays to electron or muon pairs. The measurement is based on data collected with the CMS detector corresponding to an integrated luminosity of 19.7 fb^(−1). The electroweak contribution has a significance of 3.0 standard deviations, and the measured fiducial cross section is 1.86_(−0.75)^(+0.90) (stat)_(−0.26)^(+0.34) (syst)±0.05(lumi) fb, while the summed electroweak and quantum chromodynamic total cross section in the same region is observed to be 5.94_(−1.35)^(+1.53) (stat) _(−0.37)^(+0.43) (syst) ± 0.13(lumi) fb. Both measurements are consistent with the leading-order standard model predictions. Limits on anomalous quartic gauge couplings are set based on the Zγ mass distribution.