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arXiv · 1107.1497

Lattice Determination of the Hadronic Contribution to the Muon $g-2$ using Dynamical Domain Wall Fermions

Peter Boyle·Luigi Del Debbio·Eoin Kerrane·James Zanotti
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Abstract

We present a calculation of the leading order hadronic contribution to the anomalous magnetic moment of the muon for a dynamical simulation of 2+1 flavour QCD using domain wall fermions. The electromagnetic 2-point function is evaluated on the RBC-UKQCD lattice gauge configurations and this is fitted to a continuous form motivated by models of vector dominance. We determine a robust and reliable technique for performing this fit, allowing us to extract the most accurate results possible from our ensembles. This combined with data at very light quark masses produces the result a_μ^{(2)had}=641(33)(32) x 10^{-10} at the physical point, where the first uncertainty is statistical, and the second is an estimate of systematics, which is in agreement with previous results. We outline various methods by which this calculation can and will be improved in order to compete with the accuracy of alternative techniques of deducing this quantity from experimental scattering data.

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Peter Boyle, Luigi Del Debbio, Eoin Kerrane, James Zanotti. 2011-07-07. Lattice Determination of the Hadronic Contribution to the Muon $g-2$ using Dynamical Domain Wall Fermions. https://doi.org/10.1103/physrevd.85.074504

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