论文标题
QCD的声音速度
Speed of sound in QCD matter
论文作者
论文摘要
我们系统地研究了QCD在不同条件下的QCD物质中的声音速度，在Polyakov环中的大典型集合中改进了Nambu-Jona-Lasinio（PNJL）模型。数值结果表明，声音速度对温度和化学电位等参数的依赖性可以指示QCD相变。发现了一些新的声音速度功能，例如，在低温下，$ u（d）$和$ s $ quark的声速层次结构随着化学势的增加，正方形的声速在关键区域接近几乎为零。我们还使用基本的热力学关系制定了不同定义的声音速度之间的关系。得出的一些结论可用于流体动力学模拟和散装粘度的运输系数的计算。
We systematically investigate the speed of sound in QCD matter under different conditions in the grand canonical ensemble within the Polyakov loop improved Nambu--Jona-Lasinio (PNJL) model. The numerical results indicate that the dependence of speed of sound on parameters like temperature and chemical potential can be indicative of QCD phase transition. Some new features of speed of sound are discovered, for instance, the hierarchy of sound velocity for $u(d)$ and $s$ quark at low temperature with the increasing chemical potential and the squared sound velocity approaching to almost zero in the critical region. We also formulate the relations between differently defined sound velocity using the fundamental thermodynamic relations. Some conclusions derived are useful for hydrodynamics simulation and calculation of transport coefficient of bulk viscosity.
