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Update of the electromagnetic effective coupling constant $α(M^2_Z)$

N. V. Krasnikov·R. Rodenberg
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Abstract

We recalculate the hadronic contribution to the effective electromagnetic coupling constant $α(M^2_Z)$ using quasi-analytical approximations for the cross-section of $e^{+}e^{-} \to hadrons$ proposed earlier by one of the authors(N.V.K.,Mod.Phys.Lett.A9(1994)2825). We find that $α^{-1}(M^2_Z) = 128.98 \pm 0.06$.

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N. V. Krasnikov, R. Rodenberg. 1997-11-18. Update of the electromagnetic effective coupling constant $α(M^2_Z)$. https://arxiv.org/abs/hep-ph/9711367

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