Studies of QCD in e+e- → hadrons at Ecm = 130 and 136 GeV

An analysis of the properties of hadronic final states produced in electron-positron annihilation at centre-of-mass energies of 130 and 136GeV is presented. The measurements are based on a data sample of 5.7 pb-1 collected in November 1995 with the ALEPH detector at LEP. Inclusive charged particle distributions, jet rates and event-shape distributions are measured and the results are compared with the predictions of QCD-based models. From the measured distributions quantities are determined for which the dependence on the centre-of-mass energy can be predicted by QCD, including the mean multiplicity of charged particles, the peak position of the inclusive distribution of ξ = -In xp (xp = p/pbeam), and the strong coupling constant αs. The QCD predictions are tested by comparing with corresponding measurements at Ecm = 91.2GeV and at lower energies. © Springer-Verlag 1997.