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

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 40 Z 50 Z 40 γ 50 γ < 0.28.