Scaling behaviour of μ_B/T in the STAR experiment

Heavy Ion Collisions (HIC) are investigated both theoretically and experimentally to understand the properties of nuclear matter at extreme conditions. One of the most important issues addressed in HIC is the possibility for nuclear matter to undergo a phase transitions to quark matter. At low baryon density and high temperature nuclear matter is expected to smoothly cross over to a quark gluon plasma (QGP) phase. Whereas, at high baryon density and low temperature the system is expected to have a first order phase transition. Therefore, the first-order phase transition at high baryonic chemical potential and low temperature should end at a critical end-point (CEP) as one moves towards a high temperature and low baryonic chemical potential region in the phase diagram of strongly interacting matter. The main goal of experiments of heavy ion collisions is to map the quantum chromodynamics (QCD) phase diagram in terms of temperatures and baryonic chemical potential. The beam energy scan programme at RHIC is currently investigating the location of CEP. In the near future, experiments at the FAIR (GSI) and at NICA (JINR) will also involve in such an investigation