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arXiv · hep-lat/9710048

Scaling Study of the Two-Flavor Chiral Phase Transition with the Kogut-Susskind Quark Action in Lattice QCD

JLQCD Collaboration·S. Aoki·M. Fukugita·S. Hashimoto·N. Ishizuka·Y. Iwasaki·K. Kanaya·Y. Kuramashi·H. Mino·M. Okawa·A. Ukawa·T. Yoshié
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Abstract

We report on a study of two-flavor finite-temperature chiral phase transition employing the Kogut-Susskind quark action and the plaquette gluon action in lattice QCD for a lattice with $N_t=4$ temporal size. Hybrid R simulations of $10^4$ trajectories are made at quark masses of $m_q=0.075, 0.0375, 0.02, 0.01$ in lattice units for the spatial sizes $8^3, 12^3$ and $16^3$. The spatial size dependence of various susceptibilities confirm the previous conclusion of the absence of a phase transition down to $m_q=0.02$. At $m_q=0.01$ an increase of susceptibilities is observed up to the largest volume $16^3$ explored in the present work. We argue, however, that this increase is likely to be due to an artifact of too small a lattice size and it cannot be taken to be the evidence for a first-order transition. Analysis of critical exponents estimated from the quark mass dependence of susceptibilities shows that they satisfy hyperscaling consistent with a second-order transition located at $m_q=0$. The exponents obtained from larger lattice, however, deviate significantly from both those of O(2), which is the exact symmetry group of the Kogut-Susskind action at finite lattice spacing, and those of O(4) expected from an effective sigma model analysis in the continuum limit.

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JLQCD Collaboration, S. Aoki, M. Fukugita, S. Hashimoto, N. Ishizuka, Y. Iwasaki, K. Kanaya, Y. Kuramashi, H. Mino, M. Okawa, A. Ukawa, T. Yoshié. 1997-10-12. Scaling Study of the Two-Flavor Chiral Phase Transition with the Kogut-Susskind Quark Action in Lattice QCD. https://doi.org/10.1103/physrevd.57.3910

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