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2+1 Flavor Lattice QCD with Luescher's Domain-Decomposed HMC Algorithm

CS Collaboration·Y. Kuramashi·S. Aoki·K. -I. Ishikawa·T. Ishikawa·N. Ishizuka·K. Kanaya·N. Tsutsui·M. Okawa·Y. Taniguchi·A. Ukawa·T. Yoshie
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Abstract

We report on a study of 2+1 flavor lattice QCD with the $O(a)$-improved Wilson quarks on a $16^3\times 32$ lattice at the lattice spacing $1/a\approx 2$GeV employing Luescher's domain-decomposed HMC(LDDHMC) algorithm. This is dedicated to a preliminary study for the PACS-CS project which plans to complete the Wilson-clover $N_f=2+1$ program lowering the up-down quark masses close to the physical values as much as possible. We focus on three issues: (i) how light quark masses we can reach with LDDHMC, (ii) efficiency of the algorithm compared with the conventional HMC, (iii) parameter choice for the production runs on PACS-CS.

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CS Collaboration, Y. Kuramashi, S. Aoki, K. -I. Ishikawa, T. Ishikawa, N. Ishizuka, K. Kanaya, N. Tsutsui, M. Okawa, Y. Taniguchi, A. Ukawa, T. Yoshie. 2006-10-10. 2+1 Flavor Lattice QCD with Luescher's Domain-Decomposed HMC Algorithm. https://arxiv.org/abs/hep-lat/0610063

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