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Towards a precise lattice determination of the leading hadronic contribution to (g − 2) μ

  • Michele Della Morte
  • Benjamin Jäger
  • Andreas Jüttner
  • Hartmut Wittig
Open Access
Article

Abstract

We report on our computation of the leading hadronic contribution to the anomalous magnetic moment of the muon using two dynamical flavours of non-perturbatively O(a) improved Wilson fermions. The strange quark is introduced in the quenched approximation. Partially twisted boundary conditions are applied to improve the momentum resolution in the relevant integral. Our results, obtained at three different values of the lattice spacing, allow for a preliminary study of discretization effects. We explore a wide range of lattice volumes, namely 2 fm ≤ L ≤ 3 fm, with pion masses from 600 to 280 MeV and discuss different chiral extrapolations to the physical point. We observe a non-trivial dependence of \(a_\mu^{HLO}\) on m π especially for small pion masses. The final result, \(a_\mu^{HLO} = 618\left( {64} \right) \times {10^{ - 10}}\), is obtained by considering only the quark connected contribution to the vacuum polarization. We present a detailed analysis of systematic errors and discuss how they can be reduced in future simulations.

Keywords

Lattice Gauge Field Theories Nonperturbative Effects Lattice Quantum Field Theory 

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Copyright information

© SISSA, Trieste, Italy 2012

Authors and Affiliations

  • Michele Della Morte
    • 1
  • Benjamin Jäger
    • 1
  • Andreas Jüttner
    • 2
  • Hartmut Wittig
    • 1
  1. 1.Institut für Kernphysik and Helmholtz Institut MainzJohannes Gutenberg-UniversitätMainzGermany
  2. 2.CERN, Physics Department, TH UnitGeneva 23Switzerland

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