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arXiv · hep-lat/9612025

The equation of state for two flavor QCD at N_t=6

The MILC Collaboration·C. W. Bernard·T. Blum·C. Detar·S. Gottlieb·U. M. Heller·J. E. Hetrick·L. Karkkainen·R. Rummukainen·R. L. Sugar·D. Toussaint·M. Wingate
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Abstract

We calculate the two flavor equation of state for QCD on lattices with lattice spacing a=(6T)^{-1} and find that cutoff effects are substantially reduced compared to an earlier study using a=(4T)^{-1}. However, it is likely that significant cutoff effects remain. We fit the lattice data to expected forms of the free energy density for a second order phase transition at zero-quark-mass, which allows us to extrapolate the equation of state to m_q=0 and to extract the speed of sound. We find that the equation of state depends weakly on the quark mass for small quark mass.

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The MILC Collaboration, C. W. Bernard, T. Blum, C. Detar, S. Gottlieb, U. M. Heller, J. E. Hetrick, L. Karkkainen, R. Rummukainen, R. L. Sugar, D. Toussaint, M. Wingate. 1996-12-21. The equation of state for two flavor QCD at N_t=6. https://doi.org/10.1103/physrevd.55.6861

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