Photon Production by Chiral Magnetic Effect in the Early Stage of High-Energy Nuclear Collisions

TL;DR

This study investigates photon production via the chiral magnetic effect during the early stages of high-energy nuclear collisions, modeling the process with a dynamic glasma and analyzing the resulting photon spectrum and elliptic flow.

Contribution

It introduces an event-by-event model of photon production from the chiral magnetic effect in the early collision stage using a 2+1D glasma framework.

Findings

Chiral magnetic effect has a minor impact on photon spectrum.

Photons can exhibit significant elliptic flow from this mechanism.

The model aligns with some experimental observations.

Abstract

We present an event-by-event study of photons produced by the chiral magnetic effect in the early stage of high-energy nuclear collisions. We model the early stage with an evolving, 2+1 dimensional, glasma, initialized via the McLerran-Venugopalan model. The photons are produced from the interplay of the chiral anomaly of quantum chromodynamics and the strong magnetic fields generated by the colliding nuclei. In particular, we focus on the spectrum and the elliptic flow of the produced photons. We find that the chiral magnetic effect has a minor impact on the photon spectrum compared to other production mechanisms as well as to experimental data. However, the photons produced by the present early stage mechanism can exhibit a significant elliptic flow.