Bulk first-order phase transition in three-flavor lattice QCD with O(a)-improved Wilson fermion action at zero temperature

Journal Article · Thu Sep 01 04:00:00 EDT 2005 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.72.054510· OSTI ID:20711469

Aoki, S; Iwasaki, Y ^[1]; Fukugita, M ^[2]; Hashimoto, S; Kaneko, T; Tsutsui, N ^[3]; Ishikawa, K-I; Okawa, M ^[4]; Ishizuka, N; Kanaya, K; Kuramashi, Y; Ukawa, A; Yoshie, T ^[1]; Yamada, N ^[5]

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1. Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571 (Japan)
2. Institute for Cosmic Ray Research, University of Tokyo, Kashiwa, Chiba 277-8582 (Japan)
3. High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan)
4. Department of Physics, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526 (Japan)
5. RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973 (United States)

Three-flavor QCD simulation with the O(a)-improved Wilson fermion action is made employing an exact fermion algorithm developed for an odd number of quark flavors. For the plaquette gauge action, an unexpected first-order phase transition is found in the strong coupling regime ({beta} < or approx. 5.0) at relatively heavy quark masses (m{sub PS}/m{sub V}{approx}0.74-0.87). Strong metastability persists on a large lattice of size 12{sup 3}x32, which indicates that the transition has a bulk nature. The phase gap becomes smaller toward weaker couplings and vanishes at {beta}{approx_equal}5.0, which corresponds to a lattice spacing a{approx_equal}0.1 fm. These results imply that realistic simulations of QCD with three flavors of dynamical Wilson-type fermions at lattice spacings in the range a=0.1-0.2 fm are not possible with the plaquette gauge action. Extending the study to improved gauge actions, we do not observe evidence for first-order phase transition, at least within the ({beta},{kappa}) range we explored. This suggests the possibility that the phase transition either moves away or weakens with improved gauge actions. Possible origins of the phase transition are discussed.

• OSTI ID: 20711469
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 5 Vol. 72; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ALGORITHMS
B QUARKS
C QUARKS
COMPUTERIZED SIMULATION
GAUGE INVARIANCE
LATTICE FIELD THEORY
PHASE TRANSFORMATIONS
QUANTUM CHROMODYNAMICS
REST MASS
STRONG-COUPLING MODEL
T QUARKS