The comparative analysis of channels of three \alpha-particles and ^12C nuclei production in ^16Op-collisions at 3.25 A GeV/c

New experimental data of the comparative analysis of channels of the production of three \alpha-particles and ^12C nuclei in ^16Op-collisions at 3.25 A GeV/c are submitted. It is shown, that the channel with the three \alpha-particles production is realised in a half part of events as a result of decay of an excited ^12C^* nucleus, and the rest part of the channel - by the knocking-out of one \alpha-cluster from the weakly bound residual nucleus, containing three \alpha-clusters. The modelling of the decay of an excited system on the model of isotropic phase space is justified at small values of excitation energy and, nevertheless, it allows to take the valuable additional information about the dynamics of investigated process from experimental data.