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arXiv · hep-ph/9805470

New Results on the Hadronic Contributions to alpha(M_Z) and to (g-2)_mu

M. Davier·A. Hocker
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Abstract

We reevaluate the dispersion integrals of the leading order hadronic contributions to the running of the QED fine structure constant alpha(s) at s=M_Z^2, and to the anomalous magnetic moments of the muon and the electron. Finite-energy QCD sum rule techniques complete the data from e+e- annihilation and tau decays at low energy and at the cc-bar threshold. Global quark-hadron duality is assumed in order to resolve the integrals using the Operator Product Expansion wherever it is applicable. We obtain delta_alpha_had(M_Z) = (276.3 +/- 1.6)x10^{-4} yielding alpha^{-1}(M_Z) = 128.933 +/- 0.021, and a_mu^had = (692.4 +/- 6.2)x10^{-10} with which we find for the complete Standard Model prediction a_mu^SM = (11659159.6 +/- 6.7)x10^{-10}. For the electron, the hadronic contribution reads a_e^had = (187.5 +/- 1.8)x10^{-14}.

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M. Davier, A. Hocker. 1998-05-27. New Results on the Hadronic Contributions to alpha(M_Z) and to (g-2)_mu. https://doi.org/10.1016/s0370-2693(98)00825-9

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