标题： 有限密度QCD状态方程：临界点和基于格点的$T'$-展开 显示英文标题

标题： Finite density QCD equation of state: critical point and lattice-based $T'$-expansion

摘要： 我们提出了一种新的有限重子密度下量子色动力学（QCD）状态方程（EoS）的构造方法。 我们的工作结合了最近提出的用于格点QCD结果的重整化方案以及QCD临界点处的普适临界行为。 这使得我们能够在 $0 \leq \mu_B \leq 700$ 兆电子伏特至 25 兆电子伏特 $\leq T \leq 800$ 兆电子伏特的范围内获得一组状态方程，这些方程在接近 $\mu_B=0$ 时与格点QCD结果相匹配，并且具有三维Ising模型普适类中的临界点。 临界点的位置可以在重离子碰撞束流扫描实验可及的范围内选择。 奇异性的强度和临界区域的形状使用一组标准参数来参数化。 我们施加了稳定性与因果性约束，并讨论了临界点参数选择的可用范围，发现它们超出了早期基于参数化的QCD EoS提议。 我们展示了热力学可观测量，包括重子密度、压力、熵密度、能量密度、重子磁化率和声速，覆盖了QCD相图中与实验探索相关的广泛区域。 显示英文摘要

摘要： We present a novel construction of the QCD equation of state (EoS) at finite baryon density. Our work combines a recently proposed resummation scheme for lattice QCD results with the universal critical behavior at the QCD critical point. This allows us to obtain a family of equations of state in the range $0 \leq \mu_B \leq 700$ MeV and 25 MeV $\leq T \leq 800$ MeV, which match lattice QCD results near $\mu_B=0$ while featuring a critical point in the 3D Ising model universality class. The position of the critical point can be chosen within the range accessible to beam-energy scan heavy-ion collision experiments. The strength of the singularity and the shape of the critical region are parameterized using a standard parameter set. We impose stability and causality constraints and discuss the available ranges of critical point parameter choices, finding that they extend beyond earlier parametric QCD EoS proposals. We present thermodynamic observables, including baryon density, pressure, entropy density, energy density, baryon susceptibility and speed of sound, that cover a wide range in the QCD phase diagram relevant for experimental exploration.