Out-of-equilibrium chiral magnetic effect from chiral kinetic theory
Out-of-equilibrium chiral magnetic effect from chiral kinetic theory
复制标题
DOI：
10.1016/j.physletb.2017.12.025
复制
发表时间：
2017-03
影响因子：
4.4
通讯作者：
An-dong Huang;Yin Jiang;S. Shi;J. Liao;P. Zhuang
中科院分区：
文献类型：
--
作者：
An-dong Huang;Yin Jiang;S. Shi;J. Liao;P. Zhuang
近年来，手征费米子多体系统中手征反常的宏观表现引起了人们的极大兴趣。一个值得注意的例子是手性磁效应(CME)。在重离子碰撞产生的夸克-胶子等离子体中寻找CME已经做出了热情的努力。一个关键的挑战是，在这样的碰撞中，极强的磁场可能只持续很短的时间，CME电流可能必须在夸克-胶子物质仍远离热平衡的早期阶段发生。因此，这需要在不平衡的情况下对CME进行建模。利用最近发展起来的手征动力学理论工具，我们首次对重离子碰撞预热阶段CME诱导的电荷分离进行了唯象研究。这一效应对磁场的时间依赖性非常敏感，也受初始夸克动量谱以及系统向热平衡演化的驰豫时间的影响。在目前的方法中，这种预热电荷分离被发现是适度的。
Recently there has been significant interest in the macroscopic manifestation of chiral anomaly in many-body systems of chiral fermions. A notable example is the Chiral Magnetic Effect (CME). Enthusiastic efforts have been made to search for the CME in the quark-gluon plasma created in heavy ion collisions. A crucial challenge is that the extremely strong magnetic field in such collisions may last only for a brief moment and the CME current may have to occur at so early a stage that the quark-gluon matter is still far from thermal equilibrium. This thus requires modeling of the CME in an out-of-equilibrium setting. With the recently developed theoretical tool of chiral kinetic theory, we make a first phenomenological study of the CME-induced charge separation during the pre-thermal stage in heavy ion collisions. The effect is found to be very sensitive to the time dependence of the magnetic field and also influenced by the initial quark momentum spectrum as well as the relaxation time of the system evolution toward thermal equilibrium. Within the present approach, such pre-thermal charge separation is found to be modest.