Beam energy dependence of pseudorapidity distributions of charged particles produced in relativistic heavy-ion collisions

Heavy-ion collisions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the Large Hadron Collider at CERN probe matter at extreme conditions of temperature and energy density. Most of the global properties of the collisions can be extracted from the measurements of charged-particle multiplicity and pseudorapidity (eta) distributions. We have shown that the available experimental data on beam energy and centrality dependence of eta distributions in heavy-ion (Au + Au or Pb + Pb) collisions from root s(NN) = 7.7 GeV to 2.76 TeV are reasonably well described by the AMPT model, which is used for further exploration. The nature of the eta distributions has been described by a double Gaussian function using a set of fit parameters, which exhibit a regular pattern as a function of beam energy. By extrapolating the parameters to a higher energy of root s(NN) = 5.02 TeV, we have obtained the charged-particle multiplicity densities, eta distributions, and energy densities for various centralities. Incidentally, these results match well with some of the recently published data by the ALICE Collaboration.