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arXiv · 1702.06783

Hadronic Vacuum Polarization in QCD and its Evaluation in the Euclidean

Eduardo de Rafael
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Abstract

We discuss a new technique to evaluate integrals of QCD Green's functions in the Euclidean based on their Mellin-Barnes representation. We present as a first application the evaluation of the lowest order Hadronic Vacuum Polarization (HVP) contribution to the anomalous magnetic moment of the muon $\frac{1}{2}(g_{\mu}-2)_{\rm\tiny HVP}\equiv a_{\mu}^{\rm HVP}$. It is shown that with a precise determination of the slope and curvature of the HVP function at the origin from lattice QCD (LQCD), one can already obtain a result for $a_{\mu}^{\rm HVP}$ which may serve as a test of the determinations based on experimental measurements of the $e^+ e^-$ annihilation cross-section into hadrons.

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Eduardo de Rafael. 2017-02-22. Hadronic Vacuum Polarization in QCD and its Evaluation in the Euclidean. https://doi.org/10.1103/physrevd.96.014510

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