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arXiv · hep-lat/0209073

Exploring QCD at small sea quark masses with improved Wilson-type quarks

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·Y. Taniguchi·A. Ukawa·T. Umeda·T. Yoshié
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Abstract

We explore the region of small sea quark masses below $m_{PS}/m_V=0.5$ in two-flavor QCD using a mean-field improved clover quark action and an RG-improved gauge action at $a \simeq 0.2$ fm on $12^3 \times 24$ and $16^3 \times 24$ lattices. We find that instability of the standard BiCGStab algorithm at small quark masses can be mostly removed by the BiCGStab(DS-$L$) algorithm, which employs $L$-th minimal residual polynomials with a dynamical selection of $L$. We also find singular spikes of $ΔH$ in the HMC algorithm at moderate values of $Δτ$. Nature of the spike is studied. We also study finite-size effects and chiral properties of meson 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, Y. Taniguchi, A. Ukawa, T. Umeda, T. Yoshié. 2002-09-13. Exploring QCD at small sea quark masses with improved Wilson-type quarks. https://arxiv.org/abs/hep-lat/0209073

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