Probing the equilibration of the QCD matter created in heavy-ion collisions with dileptons

TL;DR

This paper investigates the production and properties of dileptons in heavy-ion collisions at high energies, using advanced theoretical models to understand the equilibration process of QCD matter.

Contribution

It introduces a comprehensive multistage dynamical approach incorporating NLO thermal QCD rates, event-by-event initial conditions, viscous hydrodynamics, and hadronic afterburners to study dilepton production.

Findings

Quantifies the contributions of thermal, chemical, and Drell-Yan processes to dilepton yields.

Analyzes dilepton anisotropic flow and out-of-equilibrium effects in heavy-ion collisions.

Provides insights into the equilibration of QCD matter through dilepton observables.

Abstract

A systematic study of intermediate invariant mass dilepton production in Pb+Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV is performed, using next-to-leading-order (NLO) thermal QCD dilepton emission rates with a multistage dynamical approach which includes event-by-event IP-Glasma initial conditions, relativistic viscous fluid dynamics, and a hadronic afterburner. Considering dilepton yield and anisotropic flow, special attention is paid to the out-of-equilibrium aspects, both thermal and chemical, and to the contribution of the Drell-Yan process. The relative contribution of each of those different channels to dilepton observables is calculated and discussed.