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arXiv · 2301.08696

An update of Euclidean windows of the hadronic vacuum polarization

T. Blum·P. A. Boyle·M. Bruno·D. Giusti·V. Gülpers·R. C. Hill·T. Izubuchi·Y. -C. Jang·L. Jin·C. Jung·A. Jüttner·C. Kelly·C. Lehner·N. Matsumoto·R. D. Mawhinney·A. S. Meyer·J. T. Tsang
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Abstract

We compute the standard Euclidean window of the hadronic vacuum polarization using multiple independent blinded analyses. We improve the continuum and infinite-volume extrapolations of the dominant quark-connected light-quark isospin-symmetric contribution and address additional sub-leading systematic effects from sea-charm quarks and residual chiral-symmetry breaking from first principles. We find $a_\mu^{\rm W} = 235.56(65)(50) \times 10^{-10}$, which is in $3.8\sigma$ tension with the recently published dispersive result of Colangelo et al., $a_\mu^{\rm W} = 229.4(1.4) \times 10^{-10}$, and in agreement with other recent lattice determinations. We also provide a result for the standard short-distance window. The results reported here are unchanged compared to our presentation at the Edinburgh workshop of the g-2 Theory Initiative in 2022.

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T. Blum, P. A. Boyle, M. Bruno, D. Giusti, V. Gülpers, R. C. Hill, T. Izubuchi, Y. -C. Jang, L. Jin, C. Jung, A. Jüttner, C. Kelly, C. Lehner, N. Matsumoto, R. D. Mawhinney, A. S. Meyer, J. T. Tsang. 2023-01-20. An update of Euclidean windows of the hadronic vacuum polarization. https://arxiv.org/abs/2301.08696

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