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arXiv · hep-ex/0002012

QCD studies with e+e- annihilation data at 172-189 GeV

The OPAL collaboration·G Abbiendi
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Abstract

We have studied hadronic events from e+e- annihilation data at centre-of-mass energies of sqrt{s}=172, 183 and 189 GeV. The total integrated luminosity of the three samples, measured with the OPAL detector, corresponds to 250 pb^-1. We present distributions of event shape variables, charged particle multiplicity and momentum, measured separately in the three data samples. From these we extract measurements of the strong coupling alpha_s, the mean charged particle multiplicity and the peak position xi_0 in the xi_p=ln(1/x_p) distribution. In general the data are described well by analytic QCD calculations and Monte Carlo models. Our measured values of alpha_s, and xi_0 are consistent with previous determinations at sqrt{s}=MZ.

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The OPAL collaboration, G Abbiendi. 2000-02-03. QCD studies with e+e- annihilation data at 172-189 GeV. https://doi.org/10.1007/s100520050015

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