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arXiv · hep-lat/0406028

Non-perturbative O(a)-improvement of Wilson quark action in three-flavor QCD with plaquette gauge action

CP-PACS·JLQCD Collaborations·:·N. Yamada·S. Aoki·M. Fukugita·S. Hashimoto·K-I. Ishikawa·N. Ishizuka·Y. Iwasaki·K. Kanaya·T. Kaneko·Y. Kuramashi·M. Okawa·Y. Taniguchi·N. Tsutsui·A. Ukawa·T. Yoshie
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Abstract

We perform a non-perturbative determination of the O(a)-improvement coefficient c_SW for the Wilson quark action in three-flavor QCD with the plaquette gauge action. Numerical simulations are carried out in a range of β=12.0-5.2 on a single lattice size of 8^3x16 employing the Schrödinger functional setup of lattice QCD. As our main result, we obtain an interpolation formula for c_SW and the critical hopping parameter K_c as a function of the bare coupling. This enables us to remove O(a) scaling violation from physical observables in future numerical simulation in the wide range of β. Our analysis with a perturbatively modified improvement condition for c_SW suggests that finite volume effects in c_SW are not large on the 8^3x16 lattice. We investigate N_f dependence of c_SW by additional simulations for N_f=4, 2 and 0 at β=9.6. As a preparatory step for this study, we also determine c_SW in two-flavor QCD at β=5.2. At this β, several groups carried out large-scale calculations of the hadron spectrum, while no systematic determination of c_SW has been performed.

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CP-PACS, JLQCD Collaborations, :, N. Yamada, S. Aoki, M. Fukugita, S. Hashimoto, K-I. Ishikawa, N. Ishizuka, Y. Iwasaki, K. Kanaya, T. Kaneko, Y. Kuramashi, M. Okawa, Y. Taniguchi, N. Tsutsui, A. Ukawa, T. Yoshie. 2005-07-09. Non-perturbative O(a)-improvement of Wilson quark action in three-flavor QCD with plaquette gauge action. https://doi.org/10.1103/physrevd.71.054505

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