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arXiv · hep-lat/9510031

Improved Actions for QCD Thermodynamics on the Lattice

B. Beinlich·F. Karsch·E. Laermann
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Abstract

Finite cut-off effects strongly influence the thermodynamics of lattice regularized QCD at high temperature in the standard Wilson formulation. We analyze the reduction of finite cut-off effects in formulations of the thermodynamics of $SU(N)$ gauge theories with three different $O(a^2)$ and $O(a^4)$ improved actions. We calculate the energy density and pressure on finite lattices in leading order weak coupling perturbation theory ($T\rightarrow \infty$) and perform Monte Carlo simulations with improved $SU(3)$ actions at non-zero $g^2$. Already on lattices with temporal extent $N_τ=4$ we find a strong reduction of finite cut-off effects in the high temperature limit, which persists also down to temperatures a few times the deconfinement transition temperature.

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B. Beinlich, F. Karsch, E. Laermann. 1995-10-18. Improved Actions for QCD Thermodynamics on the Lattice. https://doi.org/10.1016/0550-3213(95)00681-8

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