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arXiv · 1411.0705

Lepton anomalous magnetic moments from twisted mass fermions

Florian Burger·Grit Hotzel·Karl Jansen·Marcus Petschlies
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Abstract

We present our results for the leading-order hadronic quark-connected contributions to the electron, the muon, and the tau anomalous magnetic moments obtained with four dynamical quarks. Performing the continuum limit and an analysis of systematic effects, full agreement with phenomenological results is found. To estimate the impact of omitting the quark-disconnected contributions to the hadronic vacuum polarisation we investigate them on one of the four-flavour ensembles. Additionally, the light quark contributions on the four-flavour sea are compared to the values obtained for $N_f=2$ physically light quarks. In the latter case different methods to fit the hadronic vacuum polarisation function are tested.

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Florian Burger, Grit Hotzel, Karl Jansen, Marcus Petschlies. 2014-11-03. Lepton anomalous magnetic moments from twisted mass fermions. https://arxiv.org/abs/1411.0705

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