"BECQUEREL" (JINR, LPI) - an investigation of the light radioactive nucleus fragmentation as wellas obtaining some surveying data on secondary particle charge states produced by the intermediate and heavy nucleus fragmentation. The task is to study cluster nature of nuclei and possible collective exited states of nuclear matter. The particular attention was paid to multiparticle production without exchange of quantum numbers between the colliding particles (diffraction dissociation of the nuclei), which makes it possible to "look" into the inner structure of one of the interacting nuclei. In the experiment, the nuclear photo emulsions were irradiated with radioactive He, Be, B, C, N and other secondary nuclei beams produced at JINR nuclotron, and the relevant interactions with the nuclei of photo emulsion are used for the systematical study of the structure of different neutron-lack nuclei by the same method.The PAVICOM facility opens an unique possibility to distinguish the secondary particle clusters formed in the diffraction dissociation process and to analyze the particle characteristics even in narrow collimated clusters. The event images obtained on PAVICOM clearly show a cluster structure of the nuclei diffraction dissociation. Particularly, in 2003 there were scanned more then 60 events of "BECQUEREL" experiment.