Dileptons produced during heavy-ion collisions represent a unique probe of
the QCD phase diagram, and convey information about the state of the strongly
interacting system at the moment their preceding off-shell photon is created.
In this study, we compute thermal dilepton yields from Au+Au collisions
performed at different beam energies, employing a (3+1)-dimensional dynamic
framework combined with emission rates accurate at next-to-leading order in
perturbation theory and which include baryon chemical potential dependencies.
By comparing the effective temperature extracted from the thermal dilepton
invariant mass spectrum with the average temperature of the fluid, we offer a
robust quantitative validation of dileptons as effective probe of the early
quark-gluon plasma stage.Comment: 6+2 pages, 4+2 figure