  The energy dependence of particle production sources in relativistic
heavy-ion collisions is investigated from RHIC to LHC energies. Whereas
charged-hadron production in the fragmentation sources follows a ln(s_NN/s_0)
law, particle production in the mid-rapidity gluon-gluon source exhibits a much
stronger dependence proportional to ln^3(s_NN/s_0), and becomes dominant
between RHIC and LHC energies. The production of particles with
pseudorapidities beyond the beam rapidity is also discussed.
