Measurement of the production cross section for Z gamma -> nu(nu)over-bar gamma in pp collisions at root s=7 TeV and limits on ZZ gamma and Z gamma gamma triple gauge boson couplings

A measurement of the Zγ→ννγ cross section in pp collisions at s√=7 TeV is presented, using data corresponding to an integrated luminosity of 5.0 fb^(−1) collected with the CMS detector. This measurement is based on the observation of events with an imbalance of transverse energy in excess of 130 GeV and a single photon in the absolute pseudorapidity range |η| < 1.4 with transverse energy above 145 GeV. The Zγ→ννγ production cross section is measured to be 21.1 ± 4.2 (stat.) ± 4.3 (syst.) ± 0.5 (lum.) fb, which agrees with the standard model prediction of 21.9 ± 1.1 fb. The results are combined with the CMS measurement of Zγ production in the l^+ l^− γ final state (where l is an electron or a muon) to yield the most stringent limits to date on triple gauge boson couplings: ∣h^Z_3∣<2.7×10^(−3) , ∣h^Z_4∣<1.3×10^(−5) for ZZγ and ∣h^γ_3∣<2.9×10^(−3) , ∣h^γ_4∣<1.5×10^(−5) for Zγγ couplings.