Thermal photons to dileptons ratio in the relativistic heavy-ion collision

Interaction of these charged particles produce electromagnetic (EM) radiations like real and virtual photons (lepton pairs). These radiations carry undistorted information of the dynamics since their mean free paths are large compared to the size of the system formed after the collision. Therefore, EM radiation can be used as an efficient tool to understand the initial conditions of the system and hence can be used to probe the quark gluon plasma (QGP) formation in heavy ion collisions (HIC)