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

摘要

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