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arXiv · hep-lat/0611031

QCD equation of state with 2+1 flavors of improved staggered quarks

C. Bernard·T. Burch·C. DeTar·Steven Gottlieb·L. Levkova·U. M. Heller·J. E. Hetrick·R. Sugar·D. Toussaint
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Abstract

We report results for the interaction measure, pressure and energy density for nonzero temperature QCD with 2+1 flavors of improved staggered quarks. In our simulations we use a Symanzik improved gauge action and the Asqtad $O(a^2)$ improved staggered quark action for lattices with temporal extent $N_t=4$ and 6. The heavy quark mass $m_s$ is fixed at approximately the physical strange quark mass and the two degenerate light quarks have masses $m_{ud}\approx0.1 m_s$ or $0.2 m_s$. The calculation of the thermodynamic observables employs the integral method where energy density and pressure are obtained by integration over the interaction measure.

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C. Bernard, T. Burch, C. DeTar, Steven Gottlieb, L. Levkova, U. M. Heller, J. E. Hetrick, R. Sugar, D. Toussaint. 2007-09-14. QCD equation of state with 2+1 flavors of improved staggered quarks. https://doi.org/10.1103/physrevd.75.094505

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