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Probing High-Energy Physics with High-Precision QED Measurements

Stephan Narison
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Abstract

I summarize our self-contained determinations of the lowest order hadronic contributions to the anomalous magnetic moments a_{μ,τ} of the muon and tau leptons, the running QED coupling α(M_Z) and the muonium hyperfine splitting ν. Using as a revised estimate of the light-by light scattering: a_μ(LL)=85(18) 10^{-11}, we deduce: a_μ^{SM} = 116 591 861(78) 10^{-11}, a_τ^{SM} = 117 759(7) 10^{-8}, giving: a_μ^{SM}-a_μ^{exp}=162(170) 10^{-11}. We also obtain: α^{-1}(M_Z)=128.926(25) and the Fermi energy splitting: ν_F^{SM}=4 459 031 783(229) {Hz}. Lower bounds on some eventual new physics are given, while ν_F^{SM} leads e.g. to m_μ/m_e=206.768 276(11) in remarkable agreement with the data.

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Stephan Narison. 2002-03-05. Probing High-Energy Physics with High-Precision QED Measurements. https://doi.org/10.1142/9789812776983_0016

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