Numerical study of the equation of state for two flavor QCD at non-zero   baryon density
  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 $\mu_q$ 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 $\mu_q$. 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 $\mu_q$ is increased. This suggests the presence of a critical endpoint in the $(\mu_q, T)$ plane. Moreover, we comment on the hadron resonance gas model, which explains well our simulation results below $T_c$. 
S. Ejiri, C.R. Allton, M. Doering, S.J. Hands, O. Kaczmarek, F.   Karsch, E. Laermann, K. Redlich