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arXiv · 2304.04423

Hadronic light-by-light contribution to the muon anomaly from lattice QCD with infinite volume QED at physical pion mass

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

The hadronic light-by-light scattering contribution to the muon anomalous magnetic moment, $(g-2$)/2, is computed in the infinite volume QED framework with lattice QCD. We report $a_\mu^\text{HLbL}=12.47(1.15)(0.95) \times 10^{-10}$ where the first error is statistical and the second systematic. The result is mainly based on the 2+1 flavor M\"obius domain wall fermion ensemble with inverse lattice spacing $a^{-1} = 1.73~\mathrm{GeV}$, lattice size $L=5.5~\mathrm{fm}$, and $m_\pi = 139~\mathrm{MeV}$, generated by the RBC-UKQCD collaborations. The leading systematic error of this result comes from the lattice discretization. This result is consistent with previous determinations.

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Thomas Blum, Norman Christ, Masashi Hayakawa, Taku Izubuchi, Luchang Jin, Chulwoo Jung, Christoph Lehner, Cheng Tu. 2023-04-10. Hadronic light-by-light contribution to the muon anomaly from lattice QCD with infinite volume QED at physical pion mass. https://arxiv.org/abs/2304.04423

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