Measurement of the strong coupling as from the four-jet rate in e+e− annihilation

Data from e+e− annihilation into hadrons at centre-of-mass energies between 91 GeV and 209 GeV are used to study the four-jet rate as a function of the Durham algorithm's resolution parameter ycut. 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 αs(Mz) = 0.1208 ± 0.0006(stat.) ± 0.0021(exp.) ± 0.0019(had.) ± 0.0024(scale) in agreement with the world average.