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arXiv · 0710.3468

Meson correlators in the epsilon-regime of two-flavor lattice QCD

JLQCD collaboration·H. Fukaya·S. Aoki·S. Hashimoto·T. Kaneko·H. Matsufuru·J. Noaki·K. Ogawa·T. Onogi·N. Yamada
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Abstract

We calculate the meson correlators in the $ε$-regime of two-flavor QCD. On a $16^3\times 32$ lattice with $a\sim 0.11$ fm, the lattice simulations are performed with the dynamical overlap fermions. We reduce the sea quark mass down to $\sim$ 3 MeV and the valence quark masses are taken in the range 1-4 MeV. The meson correlators in various channels are compared with the predictions of (partially quenched) chiral perturbation theory (ChPT). Including the NLO order of the $ε$-expansion, we extract the leading-order low energy constants of ChPT, the pion decay constant $F$ and the chiral condensate $Σ$, as $F=87.3(5.5)$ MeV and $Σ^{\bar{\mathrm{MS}}}=[237.8(4.0){MeV}]^3$.

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JLQCD collaboration, H. Fukaya, S. Aoki, S. Hashimoto, T. Kaneko, H. Matsufuru, J. Noaki, K. Ogawa, T. Onogi, N. Yamada. 2007-11-30. Meson correlators in the epsilon-regime of two-flavor lattice QCD. https://arxiv.org/abs/0710.3468

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