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arXiv · 1911.08123

The hadronic light-by-light scattering contribution to the muon anomalous magnetic moment from lattice QCD

Thomas Blum·Norman Christ·Masashi Hayakawa·Taku Izubuchi·Luchang Jin·Chulwoo Jung·Christoph Lehner
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Abstract

We report the first result for the hadronic light-by-light scattering contribution to the muon anomalous magnetic moment with all errors systematically controlled. Several ensembles using 2+1 flavors of physical mass Möbius domain-wall fermions, generated by the RBC/UKQCD collaborations, are employed to take the continuum and infinite volume limits of finite volume lattice QED+QCD. We find $a_μ^{\rm HLbL} = 7.87(3.06)_\text{stat}(1.77)_\text{sys}\times 10^{-10}$. Our value is consistent with previous model results and leaves little room for this notoriously difficult hadronic contribution to explain the difference between the Standard Model and the BNL experiment.

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Thomas Blum, Norman Christ, Masashi Hayakawa, Taku Izubuchi, Luchang Jin, Chulwoo Jung, Christoph Lehner. 2020-03-23. The hadronic light-by-light scattering contribution to the muon anomalous magnetic moment from lattice QCD. https://doi.org/10.1103/physrevlett.124.132002

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