Out-of-Equilibrium Chiral Magnetic Effect from Chiral Kinetic Theory

Research paper by Anping Huang, Yin Jiang, Shuzhe Shi, Jinfeng Liao, Pengfei Zhuang

Indexed on: 26 Mar '17Published on: 26 Mar '17Published in: arXiv - High Energy Physics - Phenomenology


A fundamental feature of microscopic quantum theories for massless spin-$\frac{1}{2}$ fermions is the chiral anomaly. Recently there has been significant interest in the study of macroscopic manifestation of chiral anomaly in many-body systems of such fermions through induced anomalous chiral transport processes. A notable example is the Chiral Magnetic Effect (CME) where a vector current (e.g. electric current) is generated along an external magnetic field. 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 implication for the subsequent hydrodynamic evolution will also be discussed.