Electric Charge Separation in Strong Transient Magnetic Fields

TL;DR

This paper explores how strong transient magnetic fields in heavy-ion collisions can create charge asymmetries among emitted hadrons through mechanisms like the chiral magnetic effect, without involving parity violations.

Contribution

It demonstrates the existence of charge separation mechanisms in both hadronic and partonic phases driven by magnetic fields, expanding understanding of charge asymmetries in heavy-ion collisions.

Findings

Charge asymmetry can arise from magnetic field-induced mechanisms.

Magnitude estimates of charge fluctuations are provided.

Both hadronic and partonic phases contribute to charge separation.

Abstract

We discuss various mechanisms for the creation of an asymmetric charge fluctuation with respect to the reaction plane among hadrons emitted in relativistic heavy-ion collisions. We show that such mechanisms exist in both, the hadronic gas and the partonic phases of QCD. The mechanisms considered here all require the presence of a strong magnetic field (the ``chiral magnetic effect''), but they do not involve parity or charge-parity violations. We analyze how a transient local electric current fluctuation generated by the chiral magnetic effect can dynamically evolve into an asymmetric charge distribution among the final-state hadrons in momentum space. We estimate the magnitude of the event-by-event fluctuations of the final-state charge asymmetry due to the partonic and hadronic mechanisms.