University of Mean Charged Hadron Multiplicities in Particle and Nuclear Collisions

We propose that mean charged hadron multiplicities in various particle collision processes including hadron-nucleus collisions are described in terms of a universal function F( ), where is the mean square invariant mass of the final state subsystem X which consists of all the produced hadrons other than the leading particles. Leading particle effects in general and nuclear mass effects in hadron-nucleus collisions are most important factors which deter· mine at a given incident energy. It is found that in proton-emulsion interaction the leading particle effects depend strongly on the number of heavily ionizing prongs. Within the framework of our model, the observed values of mean shower particle multiplicities in proton-emulsion interaction indicate that F( ) obeys a power-law.