Dispersions of the multiplicity distributions in the interactions of deuterons and alpha particles with emulsion nuclei at 4.5 GeV/c per nucleon

Studied is the behaviour of the equare root of dispersions of the multiplicity distributions for secondary particles depending on the average number of the particles produced in interactions of relativistic nuclei of deuteron and helium with emulsion nuclei at the 4.5 GeV/c impulse per nucleon. It is shown that for nucleus-nucleus interactions averaged with respect to the impact parameter (''average'' interactions) the data are close to the dependence for secondary π- mesons from proton-proton interactions. For events with the definite impact parameter the behaviour of the dispersion square root as a function of the average particle number differs from the analogous dependence for proton-proton interactions. The results are in a good agreement with the calculations of nucleus-nucleus interaction as a superposition of nucleon-nucleon interactions