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arXiv · 1807.06472

Lattice-based QCD equation of state at finite baryon density: Cluster Expansion Model

V. Vovchenko·J. Steinheimer·O. Philipsen·A. Pasztor·Z. Fodor·S. D. Katz·H. Stoecker
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Abstract

The QCD equation of state at finite baryon density is studied in the framework of a Cluster Expansion Model (CEM), which is based on the fugacity expansion of the net baryon density. The CEM uses the two leading Fourier coefficients, obtained from lattice simulations at imaginary $μ_B$, as the only model input and permits a closed analytic form. Excellent description of the available lattice data at both $μ_B = 0$ and at imaginary $μ_B$ is obtained. We also demonstrate how the Fourier coefficients can be reconstructed from baryon number susceptibilities.

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V. Vovchenko, J. Steinheimer, O. Philipsen, A. Pasztor, Z. Fodor, S. D. Katz, H. Stoecker. 2018-07-16. Lattice-based QCD equation of state at finite baryon density: Cluster Expansion Model. https://doi.org/10.1016/j.nuclphysa.2018.10.068

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