Rotating Synchrotron Radiation (RoSyRa): photon emission from magnetized and rotating quark-gluon plasma

TL;DR

This paper models photon emission from a rotating, magnetized quark-gluon plasma, showing how magnetic fields and rotation influence photon spectra and elliptic flow, helping explain the direct photon puzzle in heavy-ion collisions.

Contribution

It introduces a novel model of photon emission from rotating, magnetized quark-gluon plasma, incorporating finite volume effects and explaining experimental observations.

Findings

Magnetic field induces significant elliptic flow ($v_2$) at low transverse momentum.

Plasma rotation enhances synchrotron radiation from negatively charged quarks.

The model helps explain the excess of direct photons and their elliptic flow in experiments.

Abstract

This paper investigates the production of non-prompt photons originating from rotating synchrotron radiation (RoSyRa), specifically the emission of photons by a rigidly rotating quark-gluon plasma in thermal equilibrium, in the presence of an external magnetic field. We compute the non-prompt photon spectrum and its elliptic flow ($v_2$) at mid-rapidity. In particular, we investigate the finite volume effects. We find that at low transverse momentum, the magnetic field induces a significant $v_2$, while the plasma rotation boosts the synchrotron radiation of negatively charged quarks. These effects account for both the observed excess of direct photons and their elliptic flow, contributing to the resolution of the "direct photon puzzle".