Determination of alpha(s) in second order QCD from hadronic Z decays

Distributions of event shape variables obtained from 120600 hadronicZ decays measured with the DELPHI detector are compared to the predictions of QCD based event generators. Values of the strong coupling constant αs are derived as a function of the renormalization scale from a quantitative analysis of eight hadronic distributions. The final result, αs(MZ), is based on second order perturbation theory and uses two hadronization corrections, one computed with a parton shower model and the other with a QCD matrix element model.

Note:

Revised version

(2jet): final state
(3jet): final state
CERN LEP Stor
Z0: electroproduction
Z0: nonleptonic decay
Z0: width
annihilation: electron positron
approx. 91 GeV-cms
bibliography
colliding beams: electron positron

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Figures(0)

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