Measurement of the Strong Coupling alpha(s) from four-jet observations in e+e- annihilation

Data from e(+)e(-) annihilation into hadrons at centre-of-mass energies between 91 GeV and 209 GeV collected with the OPAL detector at LEP, are,used to study the four-jet rate as a function of the Durham algorithm resolution parameter y(cut). The four-jet rate is compared to next-to-leading order calculations that include the resummation of large logarithms. The strong coupling measured from the four-jet rate is alpha s(m(z)o) = 0.1182 +/- 0.0003(stat.) +/- 0.0015(exp.) +/- 0.0011(had.) +/- 0.0012(scale) +/- 0.0013(mass), in agreement with the world average. Next-to-leading order fits to the D-parameter and thrust minor event-shape observables are also performed for the first time. We find consistent results, but with significantly larger theoretical uncertainties