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Numerical study of the equation of state for two flavor QCD at non-zero baryon density

S. Ejiri·C. R. Allton·M. Doering·S. J. Hands·O. Kaczmarek·F. Karsch·E. Laermann·K. Redlich
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Abstract

We discuss the equation of state (EoS) for two flavor QCD at non-zero temperature and density. Derivatives of $\ln Z$ with respect to quark chemical potential $μ_q$ are calculated up to sixth order. From this Taylor series, the pressure, quark number density and associated susceptibilities are estimated as functions of temperature and $μ_q$. It is found that the fluctuations in the quark number density increase in the vicinity of the phase transition temperature and the susceptibilities start to develop a pronounced peak as $μ_q$ is increased. This suggests the presence of a critical endpoint in the $(μ_q, T)$ plane. Moreover, we comment on the hadron resonance gas model, which explains well our simulation results below $T_c$.

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S. Ejiri, C. R. Allton, M. Doering, S. J. Hands, O. Kaczmarek, F. Karsch, E. Laermann, K. Redlich. 2004-08-31. Numerical study of the equation of state for two flavor QCD at non-zero baryon density. https://doi.org/10.1142/9789812702159_0050

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