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# QCD studies with e+e− annihilation data at 130 and 136 GeV

University of Tokyo International Centre for Elementary Particle Physics and Department of Physics 113 Tokyo; Kobe University 657 Kobe Japan; Institute of Nuclear Research P O Box 51 H-4001 Debrecen Hungary; TRIUMF V6T 2A3 Vancouver Canada; Institute of Nuclear Research Debrecen Hungary; Lajos Kossuth University Department of Experimental Physics Debrecen Hungary; Ludwig-Maximilians-Universität München Germany
Zeitschrift für Physik C 04/1996; 72(2):191-206. DOI:10.1007/s002880050237

ABSTRACT We have studied hadronic events produced at LEP at centre-of-mass energies of 130 and 136 GeV. Distributions of event shape
observables, jet rates, momentum spectra and multiplicities are presented and compared to the predictions of several Monte
Carlo models and analytic QCD calculations. From fits of event shape and jet rate distributions toO(as2 ) + NLLA{\mathcal{O}}(\alpha _s^2 ) + NLLA QCD calculations, we determineα

s
(133 GeV)=0.110±0.005(stat.)±0.009(syst.). We measure the mean charged particle multiplicity 〈n
ch〉=23.40±0.45(stat.) ±0.47(syst.) and the position ζ0 of the peak in the ζ
p
= ln(1/x

p
) distribution ζ0=3.94±0.05(stat.)±0.11(syst.). These results are compared to lower energy data and to analytic QCD or Monte Carlo predictions
for their energy evolution.

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