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Theoretical uncertainties for measurements of alpha_s from electroweak observables

H. Stenzel
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Abstract

One of the most precise measurements of the strong coupling constant alpha_s(MZ) is obtained in the context of global analyses of precision electroweak data. This article reviews the sensitivity of different electroweak observables to alpha_s and describes the perturbative uncertainties related to missing higher orders. The complete renormalisation scale dependence for the relevant observables is calculated at next-to-next-to-leading order and a new method is presented to determine the corresponding perturbative uncertainty for measurements of alpha_s based on these observables.

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H. Stenzel. 2005-05-20. Theoretical uncertainties for measurements of alpha_s from electroweak observables. https://doi.org/10.1088/1126-6708%2F2005%2F07%2F013

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