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arXiv · 1308.4327

Four-Flavour Leading-Order Hadronic Contribution To The Muon Anomalous Magnetic Moment

Florian Burger·Xu Feng·Grit Hotzel·Karl Jansen·Marcus Petschlies·Dru B. Renner
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Abstract

We present a four-flavour lattice calculation of the leading-order hadronic vacuum polarisation contribution to the anomalous magnetic moment of the muon, $a_\mathrmμ^{\rm hvp}$, arising from quark-connected Feynman graphs. It is based on ensembles featuring $N_f=2+1+1$ dynamical twisted mass fermions generated by the European Twisted Mass Collaboration (ETMC). Several light quark masses are used in order to yield a controlled extrapolation to the physical pion mass. We employ three lattice spacings to examine lattice artefacts and several different volumes to check for finite-size effects. Incorporating the complete first two generations of quarks allows for a direct comparison with phenomenological determinations of $a_\mathrmμ^{\rm hvp}$. Our final result including an estimate of the systematic uncertainty $$a_{\mathrmμ}^{\rm hvp} = 6.74(21)(18) \cdot 10^{-8}$$ shows a good overall agreement with these computations.

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Florian Burger, Xu Feng, Grit Hotzel, Karl Jansen, Marcus Petschlies, Dru B. Renner. 2014-01-27. Four-Flavour Leading-Order Hadronic Contribution To The Muon Anomalous Magnetic Moment. https://doi.org/10.1007/jhep02(2014)099

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