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Jet Physics at LEP and World Summary of $α_s$

S. Bethke
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Abstract

Recent results on jet physics and tests of QCD from hadronic final states in $e^+e^-$ annihilation at PETRA and at LEP are reviewed, with special emphasis on hadronic event shapes, charged particle production rates, properties of quark and gluon jets and determinations of $α_s$. The data in the entire energy range from PETRA to LEP-2 are in broad agreement with the QCD predictions. The world summary of measurements of $α_s$ is updated and a detailed discussion of various methods to determine the overall error of $α_s (M_Z)$ is presented. The new world average is $α_s (M_Z) = 0.119 \pm 0.004$. The size of the error depends on the treatment of correlated uncertainties.

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S. Bethke. 1998-12-21. Jet Physics at LEP and World Summary of $α_s$. https://arxiv.org/abs/hep-ex/9812026

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