The emission of electromagnetic radiation from the early stages of relativistic heavy-ion collisions

TL;DR

This paper estimates electromagnetic radiation emitted during the early pre-equilibrium phase of relativistic heavy-ion collisions using Boltzmann equation solutions, predicting non-equilibrium photon spectra and comparing with experimental data.

Contribution

It introduces a novel approach to model early-stage photon production using the Boltzmann equation in the Fokker-Planck limit, providing new predictions for Pb+Pb collisions at 5.02 TeV.

Findings

Predicted non-equilibrium photon spectra for Pb+Pb collisions at 5.02 TeV.

Comparison of photon yields with standard sources and experimental data.

Demonstrated the significance of early-stage electromagnetic radiation in heavy-ion collisions.

Abstract

We estimate the production of electromagnetic radiation (real and virtual photons) from the early, pre-equilibrium, stage of relativistic heavy-ion collisions. The parton dynamics are obtained as a solution of the Boltzmann equation in the Fokker-Planck diffusion limit. The photon and dilepton rates are integrated and the obtained yields are compared with those from standard sources and with available experimental data. Non-equilibrium photon spectra are predicted for Pb+Pb at $\sqrt{s_{\rm NN}} = 5.02$ TeV.