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Chiral extrapolations with small sea quark mass data in two-flavor lattice QCD

PACS Collaboration·Y. Namekawa·S. Aoki·M. Fukugita·K-I. Ishikawa·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneko·Y. Kuramashi·V. I. Lesk·M. Okawa·A. Ukawa·T. Umeda·T. Yoshié
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Abstract

We present results on the light hadron spectrum and quark mass in two-flavor QCD calculated with small sea quark masses down to $m_{PS}/m_{V}=0.35$. The configurations are generated using the RG improved gauge and tadpole-improved clover quark action at $β=1.8$, where $a^{-1} \simeq 1$ GeV. Chiral extrapolations are made using not only polynomials and ChPT in the continuum but also formulae of Wilson chiral perturbation theory (WChPT) including $O(a^2)$ chiral breaking terms. We examine the viability of WChPT and its influence on quark masses.

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PACS Collaboration, Y. Namekawa, S. Aoki, M. Fukugita, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneko, Y. Kuramashi, V. I. Lesk, M. Okawa, A. Ukawa, T. Umeda, T. Yoshié. 2004-09-11. Chiral extrapolations with small sea quark mass data in two-flavor lattice QCD. https://arxiv.org/abs/hep-lat/0409043

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