0707.0392 (J. Schieck et al.)

Measurement of the Strong Coupling alpha_s from the Four-Jet Rate in
e+e- Annihilation using JADE data    [PDF]

J. Schieck, S. Bethke, O. Biebel, S. Kluth, P. A. Movilla Fernandez, C. Pahl, the JADE Collaboration

Data from e+e- annihilation into hadrons collected by the JADE experiment at centre-of-mass energies between 14 GeV and 44 GeV are used to study the four-jet event production rate as a function of the Durham jet algorithm's resolution parameter ycut. The four-jet rate is compared to QCD next-to-leading order calculations including resummation of large logarithms in the next-to-leading logarithmic approximation. The strong coupling measured from the four-jet rate is as(MZ)=0.1159+-0.0004(stat)+-0.0012(expt)+-0.0024(had)+-0.0007(theo) in agreement with the world average.

View original: http://arxiv.org/abs/0707.0392