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arXiv · 0806.4586

Low energy chiral constants from epsilon-regime simulations with improved Wilson fermions

Anna Hasenfratz·Roland Hoffmann·Stefan Schaefer
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Abstract

We present a lattice QCD calculation of the low energy constants of the leading order chiral Lagrangian. In these simulations the epsilon regime is reached by using tree-level improved nHYP Wilson fermions combined with reweighting in the quark mass. We analyze two point functions on two ensembles with lattices of size (1.85fm)^4 and (2.8fm)^4, and at several quark mass values between 4 and 20 MeV. The data are well fitted with next-to-leading order chiral perturbative formulae and predict F=90(4)MeV and Sigma^(1/3)=248(6)MeV in the MS-bar scheme at 2 GeV.

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Anna Hasenfratz, Roland Hoffmann, Stefan Schaefer. 2008-10-02. Low energy chiral constants from epsilon-regime simulations with improved Wilson fermions. https://doi.org/10.1103/physrevd.78.054511

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