  The centrality dependence of pseudorapidity distributions for charged
particles produced in Au+Au collisions at $\sqrt{s_{NN}}=130$ GeV and 200 GeV
at RHIC, and in Pb+Pb collisions at $\sqrt{s_{NN}}=2.76$ TeV at LHC are
investigated in the fireball model, assuming that the rapidity axis is
populated with fireballs following one distribution function. We assume that
the particles in the fireball fulfill the Tsallis distribution. The theoretical
results are compared with the experimental measurements and a good agreement is
found. Using these results, the pseudorapidity distributions of charged
particles produced in Pb+Pb central collisions at $\sqrt{s_{NN}}=5.02$ TeV and
10 TeV are predicted.
