Experimental data on fragmentation channels in peripheral interactions of 8 B nuclei in nuclear track emulsions are presented. A detailed analysis made it possible to justify selections of events of the electromagnetic-dissociation process 8 B → 7 Be + p and to estimate its cross section. Events of 10 C peripheral dissociation that were observed in the same exposure are described.

The dissociation features in nuclear track emulsion of 9 Be, 9,10 C, and 12 N nuclei of 1.2 A GeV energy are presented. The data presented for the nucleus 9 Be can be considered as evidence that there is a core in its structure in the form of 0 + and 2 + states of the 8 Be nucleus having roughly equal weights. Events of coherent dissociation 9 C→3 3 He associated with the rearrangement of the nucleons outside the α-clustering are identified. A pattern of the charge fragment topology in the dissociation of 10 C and 12 N nuclei is obtained for the first time. Contribution of the unbound nucleus decays to the cascade process 10 C→ 9 B→ 8 Be is identified.

Inelastic interactions of nuclei accelerated to a momentum of 4.5 GeV/c per projectile nucleon with photoemulsion nuclei have been investigated. The main features of these interactions mean ranges of 6 Li nuclei, mean multiplicities of secondaries, the isotopic composition of fragments, fragmentation channels, and the mean transverse momenta of projectile fragments have been measured.The probability of the charge-exchange reaction featuring lithium nuclei has been determined. The results obtained for the 6 Li nucleus have been compared with data for other nuclei. The observed features of 6 Li interactions with other nuclei indicate that the 6 Li structure in the form of the loosely bound system consisting of an α-particle and a deuteron cluster clearly manifests itself in these interactions. Events resulting in the coherent dissociation of 6 Li nuclei into 4 He+d, 3 He+t, and t + d + p and involving low-lying excitations of 6 Li have been observed.

The charge topology in the fragmentation of 10 C nuclei in a track nuclear emulsion at an energy of 1.2 GeV per nucleon is studied. In the coherent dissociation of 10 C nuclei, about 82% of events are associated with the channel 10 C → 2α+ 2p. The angular distributions and correlations of product fragments are presented for this channel. It is found that among 10 C → 2α+ 2p events, about 30% are associated with the process in which dissociation through the ground state of the unstable 9 Beg.s. nucleus is followed by 8 Beg.s.+ p decays.

The dissociation of relativistic 12 N nuclei having a momentum of 2 GeV/c per nucleon and undergoing the most peripheral interactions in a track emulsion is studied. The picture of charged topology of product ensembles of relativistic fragments and special features of their angular distributions are presented. DOI: 10.1134/S1063778813100074The track-emulsion method has still retained its exceptional position as a means for studying the structure of fragmentation of relativistic nuclei owing to the completeness of observation of fragment ensembles and owing to its record spatial resolution. The objective of employing a track emulsion in the Becquerel project [1] at the nuclotron of the Joint Institute for Nuclear Research (JINR, Dubna) is to study the clustering of nucleons for a wide variety of light nuclei, including radioactive ones. An analysis proves to be the most comprehensive for coherent-dissociation events, in which target fragments or mesons are not produced [2] and which, for the sake of brevity, are referred to as white stars. Since the perturbation is minimal in interactions of this type, a configuration overlap of the ground states of the nuclei being studied and the observed ensembles of fragments and nucleons manifests itself. On this basis, there arise possibilities for some kind of a tomography of the nuclear structure. The distribution of white stars with respect to the probability for the formation of various configurations shows a correlation with weights of respective cluster components of the nuclei being studied. The discovery of the contribution from unexplored and even unexpected components of deeply bound cluster states is possible on this path. This is so especially for proton-rich light nuclei. The picture of nucleon clustering in events of the coherent dissociation of the 12 N radioactive nucleus, which has yet to receive adequate study, on track-emulsion nuclei is the