2021 Impact factor 4.991
Particles and Fields

Eur. Phys. J. C 21, 423-441 (2001)
DOI: 10.1007/s100520100730

Measurement of triple gauge-boson couplings at LEP energies up to 189 GeV

The ALEPH Collaboration A. Heister and et al.

Physikalisches Institut das RWTH-Aachen, 52056 Aachen, Germany

(Received: 28 February 2001 / Published online: 24 August 2001 -© Springer-Verlag / Società Italiana di Fisica 2001 )

The triple gauge-boson couplings involving the W are determined using data samples collected with the ALEPH detector at mean centre-of-mass energies of 183 GeV and 189 GeV, corresponding to integrated luminosities of 57 pb-1 and 174 pb-1, respectively. The couplings, gZ1, $\kappa_\gamma$ and $\lambda_\gamma$, are measured using W-pair events, single-W production and single-$\gamma$ production. Each coupling is measured individually with the other two couplings fixed at their standard model value. Including ALEPH results from lower energies, the 95% confidence level intervals for the deviation to the standard model are $ -0.087 < \Delta{g}^{Z}_1 < 0.141,$ $ -0.200 < \Delta\kappa_\gamma < 0.258, { and }$ $ -0.062 < \lambda_\gamma < 0.147.$ Fits are also presented where two or all three couplings are allowed to vary. In addition, W-pair events are used to set limits on the C- or P-violating couplings gV4, gV5, ${\tilde{\kappa}_{V}}$, and ${\tilde{\lambda}_{V}}$, where V denotes either $\gamma$ or Z. No deviations from the standard model expectations are observed.

© Società Italiana di Fisica, Springer-Verlag 2001