Helium production from 84Kr-- and 197Au--emulsion interactions at high energies

The properties of the relativistic helium fragments produced in interactions of 84 Kr at 1.8 A GeV and 197 Au at 10.7 A GeV in emulsion are investigated. The experimental results are compared with those obtained from various projectiles with emulsion collisions at different energies. It is found that the multiplicity distribution of helium projectile fragments (HPFs) is well described by the Koba-Nielsen-Olesen (KNO) scaling presentation. The second Mueller moment f 2 of the HPF multiplicity distribution is independent of the projectile energy for the same projectile, but it is dependent on the projectile mass number. The value of f 2 increases with the increase of projectile mass number A p . The negative value of f 2 , when A p < 69, means that the emission of HPFs is anticorrelated, but positive value of f 2 , when A p > 69, refers to that the emission of HPFs is correlated. The non-zero f 2 moment in this experiment implies the strong correlation existing between the HPFs.