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Search for Trilinear Neutral Gauge Boson Couplings in Z-gamma production at sqrt(s)=189GeV at LEP

The OPAL collaboration·G. Abbiendi
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Abstract

The data recorded at a centre-of-mass energy of 189GeV by the OPAL detector at LEP are used to search for trilinear couplings of the neutral gauge bosons in the process e+e- --> Z-gamma. The cross-sections are measured for multihadronic events with an energetic isolated photon and for events with a high energy photon accompanied by missing energy. These cross-sections and the photon energy, polar angle and isolation angle distributions are compared to the Standard Model predictions and to the theoretical expectations of a model allowing for Z-gamma-Z and Z-gamma-gamma vertices. Since no significant deviations with respect to the Standard Model expectations are found, constraints are derived on the strength of neutral trilinear gauge couplings.

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The OPAL collaboration, G. Abbiendi. 2000-07-09. Search for Trilinear Neutral Gauge Boson Couplings in Z-gamma production at sqrt(s)=189GeV at LEP. https://doi.org/10.1007/s100520000490

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