Measurement of triple gauge boson couplings from WW production at LEP energies up to 189 GeV

TL;DR

This paper reports precise measurements of triple gauge boson couplings from W-pair production at LEP energies up to 189 GeV, confirming consistency with Standard Model predictions.

Contribution

It provides the first combined measurement of triple gauge couplings at 189 GeV, improving precision and confirming SM consistency.

Findings

Measured couplings are consistent with SM

Achieved improved precision over previous measurements

Combined data from multiple energies enhances reliability

Abstract

A measurement of triple gauge boson couplings is presented, based on W-pair data recorded by the OPAL detector at LEP during 1998 at a centre-of-mass energy of 189 GeV with an integrated luminosity of 183 pb^-1. After combining with our previous measurements at centre-of-mass energies of 161-183 GeV we obtain k_g=0.97 +0.20 -0.16, g_1^z=0.991 +0.060 -0.057 and lambda_g=-0.110 +0.058 -0.055, where the errors include both statistical and systematic uncertainties and each coupling is determined by setting the other two couplings to their SM values. These results are consistent with the Standard Model expectations.