Improved predictions for g-2 of the muon and α_{\rm QED}(M_Z^2)

K. Hagiwara; A. D. Martin; Daisuke Nomura; T. Teubner

doi:10.1016/j.physletb.2007.04.012

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Improved predictions for g-2 of the muon and α_{\rm QED}(M_Z^2)

K. Hagiwara·A. D. Martin·Daisuke Nomura·T. Teubner

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Abstract

We update the Standard Model predictions of the anomalous magnetic moment of the muon, a_μ= (g-2)/2, and the value of the QED coupling at the Z-boson mass, incorporating the new e^+e^- \to ππdata obtained by CMD-2 and KLOE, as well as the corrected SND data, and other improvements. The prediction for a_μ=11659180.4 (5.1) \times 10^{-10} is about 3 \times 10^{-10} lower than before, and has a smaller uncertainty, which corresponds to a 3.4σdeviation from the measured value. The prediction for the QED coupling is α(M_Z^2)^{-1}= 128.937 \pm 0.030.

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K. Hagiwara, A. D. Martin, Daisuke Nomura, T. Teubner. 2007-04-20. Improved predictions for g-2 of the muon and α_{\rm QED}(M_Z^2). https://doi.org/10.1016/j.physletb.2007.04.012

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