THE DISSOCIATION REACTION C-12-]3-ALPHA ON HYDROGEN, CARBON, AND TANTALUM NUCLEI AT 4.2 GEV C PER NUCLEON/

Cross sections of the carbon coherent dissociation into three alpha pa rticles on hydrogen, carbon, and tantalum nuclei at p0 = 4.2 GeV/c per nucleon are estimated. The A-dependence of the cross sections is foun d to be consistent with the diffraction mechanism of the reaction. The momentum and correlation characteristic of alpha particles are consid ered both in the laboratory and center-of-mass frames. Evidence that t he decay is of nonstatistical nature is obtained. The ''temperature'' of a C-12 nucleus undergoing fragmentation is estimated.