Anomalous coupling at LEP 2

The Standard Model of electroweak interactions is a non-abelian theory that predicts the existence of self couplings of its gauge bosons. The production close to the threshold of W pairs at LEP 2 makes it the ideal environment to investigate these triple vertices and the possible anomalous values of their couplings. The four LEP collaboration have applied several methods for the determination of the so called anomalous couplings from data collected in 1996 at centre of mass energies of 161- 172 GeV. The measured values have been found to be in agreement with the Standard Model predictions and to indicate the existence, with more than the 95% of confidence level, of the WWZ vertex.