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The measurement of alpha_s from event shapes with the DELPHI detector at the highest LEP energies

The DELPHI Collaboration·J. Abdallah
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Abstract

Hadronic event shape distributions are determined from data in e+e- collisions between 183 and 207 GeV. From these the strong coupling alpha_s is extracted in O(alpha_s^2), NLLA and matched O(alpha_s^2)+NLLA theory. Hadronisation corrections evaluated with fragmentation model generators as well as an analytical power ansatz are applied. Comparing these measurements to those obtained at and around M_Z allows a combined measurement of alpha_s from all DELPHI data and a test of the energy dependence of the strong coupling.

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The DELPHI Collaboration, J. Abdallah. 2004-06-02. The measurement of alpha_s from event shapes with the DELPHI detector at the highest LEP energies. https://doi.org/10.1140/epjc%2Fs2004-01889-x

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