Search for ZZ and Zγ^* production in pp‾ collisions at √s=1.96 TeV and limits on anomalous ZZZ and ZZγ^* couplings

Abstract

We present a study of μ μ μ μ , eeee, and μ μ ee events using 1fb^-1 of data collected with the D0 detector at the Fermilab Tevatron pp‾ Collider at √s=1.96 TeV. Requiring the lepton pair masses to be greater than 30 GeV, we observe one event, consistent with the expected background of 0.13± 0.03 events and with the predicted standard model ZZ and Zγ^* production of 1.71± 0.15 events. We set an upper limit on the ZZ and Zγ^* cross section of 4.4 pb at the 95% C.L. We also derive limits on anomalous neutral trilinear ZZZ and ZZγ^* gauge couplings. The one-parameter 95% C.L. coupling limits with a form-factor scale Λ=1.2 TeV are -0.28< f₄₀^Z< 0.28, -0.31< f₅₀^Z< 0.29, -0.26< f₄₀^γ< 0.26, and -0.30< f₅₀^γ< 0.28.