Some peculiarities of formation of 4He nuclei in 16Op collisions at 3.25A GeV/c

The new experimental data on dependences of the mean multiplicities and kinematical characteristics of 4He nuclei, formed in 16Op collisions at 3.25A GeV/c, on degree of excitation of the fragmenting nucleus are presented. It is shown that the initial (α cluster) structure of oxygen nucleus is retained at small excitation levels. It is established that the kinematical characteristics of 1H, 2H, 3H and 3He fragments do not depend on availability or absence of α particles in a collision event, which indicates the independence of mechanisms of formation of such fragments and 4He nuclei.