Improved Evaluation of the Hadronic Vacuum Polarization Contributions to Muon $g-2$ and $\barα_{\rm QED}(M_Z)$ Using High Order QCD Calculations

K. Adel; F. J. Ynduráin

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arXiv · hep-ph/9509378

Improved Evaluation of the Hadronic Vacuum Polarization Contributions to Muon $g-2$ and $\barα_{\rm QED}(M_Z)$ Using High Order QCD Calculations

K. Adel·F. J. Ynduráin

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Abstract

We use recently evaluated radiative and nonperturbative corrections to production of heavy quarks by a vector current to give very precise theoretical calculations of the high energy ($t^{1/2}\geq \sqrt{2}$ GeV) imaginary part of the photon vacuum polarization function, ${\rm Im}Π(t)$. This allows us to improve the corresponding contributions to the muon (or any other lepton) $g-2$ anomaly and to the running QED constant on the $Z$, $\barα_{\rm QED}(M_Z)$. This decreases the error in the evaluations by a factor between two and six for the high energy contribution, and by some 50\% for the overall result. We find for the hadronic contributions $a_h=6993.4\pm110.0\times10^{-11}$ and $Δα_h=272.59\pm4.09\times10^{-4}\,.$

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K. Adel, F. J. Ynduráin. 1995-09-25. Improved Evaluation of the Hadronic Vacuum Polarization Contributions to Muon $g-2$ and $\barα_{\rm QED}(M_Z)$ Using High Order QCD Calculations. https://arxiv.org/abs/hep-ph/9509378

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