Centrality dependence of particle emission in nucleus-nucleus collisions at the nucleon and quark levels

A theoretical analysis of the particle multiplicity as a function of centrality is made with respect to particle emission sources (wounded nucleons, quarks) in a wide energy range from RHIC to LHC. The Monte Carlo Glauber model is used for heavy ion collisions. It is shown that scaling in terms of the number of wounded quarks is fulfilled at all energies. This effect is associated with an increase of the wounded quarks pairs in the transverse plane with a decrease of the colliding nuclei impact parameter. A wounded quark emits the same number of particles regardless of the colliding nuclei impact parameter.