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arXiv · 1407.2923

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

Thomas Blum·Saumitra Chowdhury·Masashi Hayakawa·Taku Izubuchi
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Abstract

The form factor that yields the light-by-light scattering contribution to the muon anomalous magnetic moment is computed in lattice QCD+QED and QED. A non-perturbative treatment of QED is used and is checked against perturbation theory. The hadronic contribution is calculated for unphysical quark and muon masses, and only the diagram with a single quark loop is computed. Statistically significant signals are obtained. Initial results appear promising, and the prospect for a complete calculation with physical masses and controlled errors is discussed.

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Thomas Blum, Saumitra Chowdhury, Masashi Hayakawa, Taku Izubuchi. 2014-07-10. Hadronic light-by-light scattering contribution to the muon anomalous magnetic moment from lattice QCD. https://doi.org/10.1103/physrevlett.114.012001

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