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arXiv · hep-ph/9608366

Nonfactorizable QCD and Electroweak Corrections to the Hadronic Z Boson Decay Rate

Andrzej Czarnecki·Johann H. Kühn
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Abstract

We present an analysis of two-loop mixed QCD and electroweak corrections to the decay of the Z boson into light quarks. We find that the naive factorization of QCD and electroweak corrections does not describe correctly the two-loop effects. The nonfactorizable corrections shift the width of the Z boson by approximately -0.55(3) MeV and increase the central value of the strong coupling constant determined at LEP by 0.001.

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Andrzej Czarnecki, Johann H. Kühn. 1997-11-25. Nonfactorizable QCD and Electroweak Corrections to the Hadronic Z Boson Decay Rate. https://doi.org/10.1103/physrevlett.77.3955

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