Probing the equilibration of the QCD matter created in heavy-ion collisions with dileptons
Xiang-Yu Wu, Lipei Du, Charles Gale, Sangyong Jeon
Abstract
A systematic study of intermediate invariant mass dilepton production in $\mathrm{Pb}+\mathrm{Pb}$ collisions at $\sqrt{{s}_{NN}}=5.02\phantom{\rule{4pt}{0ex}}\mathrm{TeV}$ 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.