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arXiv · hep-ph/9411377

A determination of the QED coupling at the $Z$ pole

A. D. Martin·D. Zeppenfeld
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Abstract

We critically examine the evaluation of the hadronic contribution to the running of the QED coupling, $α$, from $Q^2=0$ to $Q^2=M_Z^2$. Using data for $e^+e^-\to{}$hadrons we find that $α(M_Z^2)^{-1} = 128.99\pm 0.06$, as compared to the existing value of $128.87\pm 0.12$.

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A. D. Martin, D. Zeppenfeld. 1994-12-08. A determination of the QED coupling at the $Z$ pole. https://doi.org/10.1016/0370-2693(94)01659-z

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