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Measurement of the Strong Coupling alpha_S from the Four-Jet Rate in e+e- annihilation

Jochen Schieck
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Abstract

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 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 0.1208 +-0.0006(stat.)+-0.0021(exp.)+-0.0019(had.)+-0.0024(scale) in agreement with the world average.

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Jochen Schieck. 2004-12-20. Measurement of the Strong Coupling alpha_S from the Four-Jet Rate in e+e- annihilation. https://doi.org/10.1016/j.nuclphysbps.2005.08.002

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