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arXiv · 0809.2842

Fixed Scale Approach to Equation of State in Lattice QCD

T. Umeda·S. Ejiri·S. Aoki·T. Hatsuda·K. Kanaya·Y. Maezawa·H. Ohno
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Abstract

A new approach to study the equation of state in finite-temperature QCD is proposed on the lattice. Unlike the conventional method in which the temporal lattice size $N_t$ is fixed, the temperature $T$ is varied by changing $N_t$ at fixed lattice scale. The pressure of the hot QCD plasma is calculated by the integration of the trace anomaly with respect to $T$ at fixed lattice scale. This "$T$-integral method" is tested in quenched QCD on isotropic and anisotropic lattices and is shown to give reliable results especially at intermediate and low temperatures.

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T. Umeda, S. Ejiri, S. Aoki, T. Hatsuda, K. Kanaya, Y. Maezawa, H. Ohno. 2009-02-15. Fixed Scale Approach to Equation of State in Lattice QCD. https://doi.org/10.1103/physrevd.79.051501

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