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arXiv · 1912.01950

Lattice calculation of the hadronic leading order contribution to the muon $g-2$

H. Wittig·A. Gérardin·Marco Cè·G. von Hippel·B. Hörz·H. B. Meyer·K. Miura·D. Mohler·K. Ottnad·A. Risch·T. San José·J. Wilhelm
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Abstract

The persistent discrepancy of about 3.5 standard deviations between the experimental measurement and the Standard Model prediction for the muon anomalous magnetic moment, $a_\mu$, is one of the most promising hints for the possible existence of new physics. Here we report on our lattice QCD calculation of the hadronic vacuum polarisation contribution $a_\mu^{\rm hvp}$, based on gauge ensembles with $N_f=2+1$ flavours of O($a$) improved Wilson quarks. We address the conceptual and numerical challenges that one encounters along the way to a sub-percent determination of the hadronic vacuum polarisation contribution. The current status of lattice calculations of $a_\mu^{\rm hvp}$ is presented by performing a detailed comparison with the results from other groups.

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H. Wittig, A. Gérardin, Marco Cè, G. von Hippel, B. Hörz, H. B. Meyer, K. Miura, D. Mohler, K. Ottnad, A. Risch, T. San José, J. Wilhelm. 2019-12-04. Lattice calculation of the hadronic leading order contribution to the muon $g-2$. https://doi.org/10.1051/epjconf/202023401016

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