QCD equation of state matched to lattice data and exhibiting a critical point singularity
QCD equation of state matched to lattice data and exhibiting a critical point singularity
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DOI：
10.1103/physrevc.101.034901
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发表时间：
2018-05
影响因子：
3.1
通讯作者：
P. Parotto;M. Bluhm;D. Mroczek;M. Nahrgang;J. Noronha-Hostler;K. Rajagopal;C. Ratti;T. Schaefer
中科院分区：
文献类型：
--
作者：
P. Parotto;M. Bluhm;D. Mroczek;M. Nahrgang;J. Noronha-Hostler;K. Rajagopal;C. Ratti;T. Schaefer
建立了温度范围为30MeV≤T≤800MeV，化学势范围为0≤μB≤450MeV的QCD的态方程。这些状态方程与现有的晶格QCD结果匹配到0 (μB4)，并在每个方程中放置了三维（3D） Ising模型普适类的临界点。这个临界点的位置可以在相对论重离子对撞机第二次束流能量扫描所覆盖的化学势范围内选择。我们讨论了将Ising模型映射到QCD时产生的自由参数的可能选择。我们对压力、熵密度、重子密度、能量密度和声速的计算结果可以作为重离子碰撞产生的火球流体动力学模拟的输入。我们还给出了热平衡中重子数第二累积量的结果，显示了它在临界点处的散度。在未来，将RHIC数据与建立在我们所构建的模型状态方程上的流体动力学模拟的输出进行比较，包括涨落观测值的计算，可以用来定位QCD相图中的临界点，如果有的话。
We construct a family of equations of state for QCD in the temperature range 30MeV≤T≤800MeV and in the chemical potential range 0≤μB≤450MeV. These equations of state match available lattice QCD results up to O(μB4) and in each of them we place a critical point in the three-dimensional (3D) Ising model universality class. The position of this critical point can be chosen in the range of chemical potentials covered by the second Beam Energy Scan at the Relativistic Heavy Ion Collider. We discuss possible choices for the free parameters, which arise from mapping the Ising model onto QCD. Our results for the pressure, entropy density, baryon density, energy density, and speed of sound can be used as inputs in the hydrodynamical simulations of the fireball created in heavy ion collisions. We also show our result for the second cumulant of the baryon number in thermal equilibrium, displaying its divergence at the critical point. In the future, comparisons between RHIC data and the output of the hydrodynamic simulations, including calculations of fluctuation observables, built upon the model equations of state that we have constructed may be used to locate the critical point in the QCD phase diagram, if there is one to be found.