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Measurement of alpha_s(M_Z^2) from Hadronic Event Observables at the Z^0 Resonance

K. Abe
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Abstract

The strong coupling alpha_s(M_Z^2) has been measured using hadronic decays of Z^0 bosons collected by the SLD experiment at SLAC. The data were compared with QCD predictions both at fixed order, O(alpha_s^2), and including resummed analytic formulae based on the next-to-leading logarithm approximation. In this comprehensive analysis we studied event shapes, jet rates, particle correlations, and angular energy flow, and checked the consistency between alpha_s(M_Z^2) values extracted from these different measures. Combining all results we obtain alpha_s(M_Z^2) = 0.1200 \pm 0.0025(exp.) \pm 0.0078(theor.), where the dominant uncertainty is from uncalculated higher order contributions.

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K. Abe. 1997-07-23. Measurement of alpha_s(M_Z^2) from Hadronic Event Observables at the Z^0 Resonance. https://doi.org/10.1103/physrevd.51.962

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