Chiral Magnetic Effect in Heavy Ion Collisions

TL;DR

This paper reviews the theoretical background and experimental efforts to detect the Chiral Magnetic Effect in heavy ion collisions, where strong magnetic fields and gluonic topological fluctuations may induce observable charge separation.

Contribution

It provides a concise overview of the current status and challenges in searching for the CME in heavy ion collision experiments.

Findings

Experimental efforts have yet to conclusively confirm CME signals.

Strong magnetic fields are present during early collision stages.

Gluonic topological fluctuations can generate chirality imbalance.

Abstract

The Chiral Magnetic Effect (CME) is a remarkable phenomenon that stems from highly nontrivial interplay of QCD chiral symmetry, axial anomaly, and gluonic topology. It is of fundamental importance to search for the CME in experiments. The heavy ion collisions provide a unique environment where a hot chiral-symmetric quark-gluon plasma is created, gluonic topological fluctuations generate chirality imbalance, and very strong magnetic fields $|\vec{\bf B}|\sim m_\pi^2$ are present during the early stage of such collisions. Significant efforts have been made to look for CME signals in heavy ion collision experiments. In this contribution we give a brief overview on the status of such efforts.