论文标题
扩展夸克系统中的手性相变
Chiral Phase Transition in an Expanding Quark System
论文作者
论文摘要
我们研究了手性对称性的影响，该对称的影响是通过考虑非平衡膨胀夸克 - 易夸克系统中的手性相变而变化的。手性对称性用平均阶阶参数描述，其值是自洽方程的解决方案，并通过VLASOV方程中的力项影响系统的时空演变。 vlasov方程和间隙方程是同时且连续求解的，以实现纵向增强和横向旋转不变的系统。这个数值框架使我们能够仔细研究相变和碰撞如何影响系统的演变。观察到，手性相变的流速会导致扭结，这是由弗拉索夫方程中的力项引起的。较大的敏感性增强了扭结，并倾向于通过非平衡效应来平滑。空间相边界是夸克的“墙”，因为具有低动量的夸克被反弹，而具有高动量的夸克则穿过墙壁，但会放慢脚步。
We investigate the influence of chiral symmetry which varies along the space-time evolution of the system by considering the chiral phase transition in an non-equilibrium expanding quark-antiquark system. The chiral symmetry is described by the mean field order parameter, whose values is the solution of a self-consistent equation, and affects the space-time evolution of the system through the force term in the Vlasov equation. The Vlasov equation and the gap equation are solved concurrently and continuously for a longitudinal boost-invariant and transversely rotation-invariant system. This numerical framework enables us to carefully investigate how the phase transition and collision affect the evolution of the system. It is observed that the chiral phase transition gives rise to a kink in the flow velocity, which is caused by the force term in the Vlasov equation. The kink is enhanced by larger susceptibility and tends to be smoothed out by non-equilibrium effect. The spatial phase boundary appears as a "wall" for the quarks, as the quarks with low momentum are bounced back, while those with high momentum go through the wall but are slowed down.
