Observation of scaling in nucleus-nucleus interactions at ultra-relativistic energies

The minimum bias events produced by interactions of 32S ions at 200 GeV/n and 16O ions at 200 and 60 GeV/n with emulsion target exhibit scaling not only in multiplicity distributions of the produced particles but also in their pseudorapidity distributions in the target (for all projectiles) as well as in the projectile rest frames (for 16O projectiles). Similar scalings are also seen in central events of 16O beams in their corresponding pseudorapidity distributions. The data agree well with the predictions of the Lund model FRITIOF. (orig.)