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arXiv · 2211.15581

Coordinate-space calculation of the window observable for the hadronic vacuum polarization contribution to $(g-2)_\mu$

En-Hung Chao·Harvey B. Meyer·Julian Parrino
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Abstract

The `intermediate window quantity' of the hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon allows for a high-precision comparison between the data-driven approach and lattice QCD. The existing lattice results, which presently show good consistency among each other, are in strong tension with the data-driven determination. In order to check for a potentially common source of systematic error of the lattice calculations, which are all based on the time-momentum representation (TMR), we perform a calculation using a Lorentz-covariant coordinate-space (CCS) representation. We present results for the isovector and the connected strange-quark contributions to the intermediate window quantity at a reference point in the $(m_\pi,m_K)$ plane, in the continuum and infinite-volume limit, based on four different lattice spacings. Our results are in good agreement with those of the recent TMR-based Mainz-CLS publication.

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En-Hung Chao, Harvey B. Meyer, Julian Parrino. 2022-11-28. Coordinate-space calculation of the window observable for the hadronic vacuum polarization contribution to $(g-2)_\mu$. https://doi.org/10.1103/physrevd.107.054505

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