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Low energy hadronic contribution to the QED vacuum polarization

H. Burkhardt·B. Pietrzyk
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Abstract

Recent improvements in the low energy e+e- annihilation data and their influence on the determination of the hadronic contribution to the running of the QED fine structure constant at m_Z are discussed. Using CMD-2 and KLOE measurements in the rho region we obtain Delta alpha(5)_had(s) = 0.02758 +/- 0.00035 at s = m_Z^2.

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H. Burkhardt, B. Pietrzyk. 2005-06-30. Low energy hadronic contribution to the QED vacuum polarization. https://doi.org/10.1103/physrevd.72.057501

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