Two and three particle pseudo-rapidity correlations among the relativistic particles in nucleus-nucleus collisions at relativistic energies

Two and three particle short-range pseudo-rapidity correlations among the relativistic produced particles in 12 A GeV 4He-, 3.7 A GeV 16O- and 1.7 A GeV 84Kr-emulsion interactions are investigated. The dependance of the normalized correlation functions upon the impact parameter, target size and azimuthal angle are discussed. The strong two particle short-range pseudo-rapidity correlation is observed in backward direction in target rest frame, which can be explained by the cumulative pions production. Finally the cumulative pseudo-rapidity gap distribution and hence the cluster characteristics, the pseudo-rapidity width distribution and the maximum pseudo-rapidity gap distribution are presented.