Unstable nuclei in dissociation of light stable and radioactive nuclei in nuclear track emulsion

A role of the unstable nuclei ⁶Be, ⁸Be and ⁹B in the dissociation of relativistic nuclei ^7,9Be, ¹⁰B and ^10,11C is under study on the basis of nuclear track emulsion exposed to secondary beams of the JINR Nuclotron. Contribution of the configuration ⁶Be + n to the ⁷Be nucleus structure is 8 ± 1% which is near the value for the configuration ⁶Li + p. Distributions over the opening angle of α-particle pairs indicate to a simultaneous presence of virtual ⁸Be_g.s. and ⁸Be₂₊ states in the ground states of the ⁹Be and ¹⁰C nuclei. The core ⁹B is manifested in the ¹⁰C nucleus with a probability of 30 ± 4%. Selection of the ¹⁰C "white" stars accompanied by ⁸Be_g.s. (⁹B) leads to appearance in the excitation energy distribution of 2α2p "quartets" of the distinct peak with a maximum at 4.1 ± 0.3 MeV. ⁸Be_g.s. decays are presented in 24 ± 7% of 2He + 2H events of the ¹¹C coherent dissociation and 27 ± 11% of the 3He ones. The channel ⁹B + H amounts 14 ± 3%. The ⁸B_g.s. nucleus is manifested in the coherent dissociation ¹⁰B → 2He + H with a probability of 25 ± 5% including 13 ± 3% of ⁹B decays. A probability ratio of the mirror channels ⁹B + n and ⁹Be + p is estimated to be 10 ± 1.