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arXiv · hep-ex/0402036

Measurement of Triple-Gauge-Boson Couplings of the W Boson at LEP

L3 Collaboration
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Abstract

The CP-conserving triple-gauge-boson couplings, g1Z, kappa_gamma, lambda_gamma, g5Z, kappa_Z and lambda_Z are measured using hadronic and semi-leptonic W-pair events selected in 629 pb-1 of data collected at LEP with the L3 detector at centre-of-mass energies between 189 and 209 GeV. The results are combined with previous L3 measurements based on data collected at lower centre-of-mass energies and with the results from single-W production and from events with a single-photon and missing energy. Imposing the constraints kappa_Z = g1Z - tan^2(theta_W) (kappa_gamma-1) and lambda_Z = lambda_gamma, we obtain for the C and P conserving couplings the results: g1Z = 0.966 +/- 0.033 (stat.) +/- 0.015 (syst.) kappa_gamma = 1.013 +/-0.066 (stat.) +/- 0.026 (syst.) lambda_gamma = -0.021 +/- 0.035 (stat.) +/-0.017 (syst.). Results from the analysis of fully leptonic W-pair decays are also given. All results are in agreement with the Standard Model expectations and confirm the existence of self-couplings among electroweak gauge bosons.

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L3 Collaboration. 2004-02-25. Measurement of Triple-Gauge-Boson Couplings of the W Boson at LEP. https://doi.org/10.1016/j.physletb.2004.02.045

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