Eur. Phys. J. C 16, 185-210
QCD studies with
The OPAL Collaboration
G. Abbiendi2 - et al.
2 Dipartimento di Fisica dell' Università di Bologna and INFN,
40126 Bologna, Italy
Received: 17 December 1999 / Published online: 18 May 2000 - © Springer-Verlag 2000
We have studied hadronic events from annihilation data at centre-of-mass energies of 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 , the mean charged particle multiplicity and the peak position in the distribution.
In general the data are described well by analytic QCD calculations and Monte Carlo models. Our measured values of , and are consistent with previous determinations at = .
Copyright Società Italiana di Fisica, Springer-Verlag 2000