QCD equation of state with almost physical quark masses

Journal Article · Tue Jan 01 00:00:00 EST 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.77.014511· OSTI ID:21035732

Cheng, M; Christ, N H; Mawhinney, R D ^[1]; Datta, S ^[2]; Heide, J van der; Kaczmarek, O; Laermann, E; Miao, C ^[3]; Jung, C; Schmidt, C; Soeldner, W ^[4]; Karsch, F ^[3]; Petreczky, P ^[4]; Petrov, K ^[5]; Umeda, T ^[6]

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1. Physics Department, Columbia University, New York, New York 10027 (United States)
2. Department of Theoretical Physics, Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India)
3. Fakultaet fuer Physik, Universitaet Bielefeld, D-33615 Bielefeld (Germany)
4. Physics Department, Brookhaven National Laboratory, Upton, New York 11973 (United States)
5. Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen (Denmark)
6. Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571 (Japan)

We present results on the equation of state in QCD with two light quark flavors and a heavier strange quark. Calculations with improved staggered fermions have been performed on lattices with temporal extent N{sub {tau}}=4 and 6 on a line of constant physics with almost physical quark mass values; the pion mass is about 220 MeV, and the strange quark mass is adjusted to its physical value. High statistics results on large lattices are obtained for bulk thermodynamic observables, i.e. pressure, energy and entropy density, at vanishing quark chemical potential for a wide range of temperatures, 140 MeV{<=}T{<=}800 MeV. We present a detailed discussion of finite cutoff effects which become particularly significant for temperatures larger than about twice the transition temperature. At these high temperatures we also performed calculations of the trace anomaly on lattices with temporal extent N{sub {tau}}=8. Furthermore, we have performed an extensive analysis of zero temperature observables including the light and strange quark condensates and the static quark potential at zero temperature. These are used to set the temperature scale for thermodynamic observables and to calculate renormalized observables that are sensitive to deconfinement and chiral symmetry restoration and become order parameters in the infinite and zero quark mass limits, respect0011ive.

• OSTI ID: 21035732
• Journal Information: Physical Review. D, Particles Fields, Vol. 77, Issue 1; Other Information: DOI: 10.1103/PhysRevD.77.014511; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
CHIRAL SYMMETRY
D QUARKS
ENTROPY
EQUATIONS OF STATE
FLAVOR MODEL
MEV RANGE
ORDER PARAMETERS
PIONS
POTENTIALS
QUANTUM CHROMODYNAMICS
REST MASS
S QUARKS
U QUARKS