Centrality dependence of mid-rapidity charged particles density in relativistic heavy ion collisions – energy scaling

Abstract

As far as details on the "Relativistic Heavy Ion Collisions – Expectations,Experimental Facts and Future Plans" lecture could be found on the Summer School web site,the present contribution will summarize the results considered to be of general interest, i.e. theenergy scaling of centrality dependence of mid-rapidity charged particles density in relativisticheavy ion collisions, presented in the second part of the lecture, in the section dedicated tothe global observables. The comparison of charged particle multiplicity in heavy ion centralcollisions and e+e− as a function of √s, including the latest results obtained at LHC in Pb+Pbcollisions at 2.76 is followed by the energy scaling of the pseudo-rapidity charged particle densityin central rapidity as a function of centrality.