Measurement of triple gauge-boson couplings in e+e- collisions from 183 to 209 GeV

Triple gauge-boson couplings involving W-pairs are determined using data samples collected with the ALEPH detector at centre-of-mass energies between 183 and 209 gev, corresponding to integrated luminosities of 684 pb-1. The couplings, g1z, kg and lg, are measured using an optimal observable method for W-pair events. Each coupling is measured individually while the two others are fixed at their Standard Model value. Including single-W and single-gamma$ production, 95% confidence level intervals are: 0.965 < g1z < 1.099 0.861 < kg < 1.140 -0.048 < lg < 0.081 Results are also presented for the cases where two or all three couplings are allowed to vary. An additional analysis using W-pair events is performed to set limits on the real and imaginary parts of all 14 triple gauge-boson couplings and to perform an indirect search for a techni-rho resonance. No deviations from the Standard Model expectations are observed and the lower limit on the techni-rho mass is 625 GeV at 95% C.L.