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Measurement of the $ZZγ$ and $Zγγ$ Couplings in $p\bar p$ Collisions at $\sqrt{s} = 1.8$ TeV

S. Abachi
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Abstract

We have directly measured the ZZ-gamma and Z-gamma-gamma couplings by studying p pbar --> l+ l- gamma + X, (l = e, mu) events at the CM energy of 1.8$ TeV with the D0 detector at the Fermilab Tevatron Collider. A fit to the transverse energy spectrum of the photon in the signal events, based on the data set corresponding to an integrated luminosity of 13.9 pb^-1 ($13.3 pb^-1) for the electron (muon) channel, yields the following 95% confidence level limits on the anomalous CP-conserving ZZ-gamma couplings: -1.9 < h^Z_30 < 1.8 (h^Z_40 = 0), and -0.5 < h^Z_40 < 0.5 (h^Z_30 = 0), for a form-factor scale Lambda = 500 GeV. Limits for the Z-gamma-gamma$ couplings and CP-violating couplings are also discussed.

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S. Abachi. 1995-03-13. Measurement of the $ZZγ$ and $Zγγ$ Couplings in $p\bar p$ Collisions at $\sqrt{s} = 1.8$ TeV. https://doi.org/10.1103/physrevlett.75.1028

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