Forward-backward correlation and cluster size in p-p collisions at 400 GeV/c

The pseudorapidity distribution of charged particles in pp collisions at 400 GeV/c has been measured by using LEBC films at SPS. The forward-backward multiplicity correlation strength in full phase space, central and off-central ranges of the pseudo-rapidity are calculated. The correlation strength is obtained versus pseudorapidity window size. The cluster size is extracted by fitting the cluster model to the experimental data. It is calculated with and without taking the leading-particle effect into account. The results show that the effect of the leading particle on the cluster size is considerable.