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Information × Registration Number 0219U001386, 0116U004452 , R & D reports Title Study of lowenergy part of the excitation spectra of helium isotopes popup.stage_title Head Povoroznyk Orest, Registration Date 28-01-2019 Organization Sceintific Center "Inststute for nuclear reaseach National Academy of sciences Ukraine popup.description2 The purpose of the study of the energy parameters of low energy unbound levels of such isotopes of helium as 5He and 6He is the first of which has two cluster structures and the second three-particle structure, that is, the removal of excitation occurs by decomposition into two particles (? + n), and in the second on three clusters ( + n + n). Experimental approaches represent a kinematically complete study of three-particle reactions of 2H( , p) n, 3H ( , d ) n, and for the 6Нe nucleus, the investigation of 4-particle 3Н+ 'p+ +n+n reaction by measuring and analyzing as inclusive two-dimensional ((ЕpхЕ )) spectra of p? - coincidences The subject of the study is unbound states of light nuclei with A = 5 (5He, 5Li). The purpose of this stage is to determine the structure of the three-particle unbound low-excited energy states of the 6He nucleus, the de-excitation of which occurs by decae into three parts + n + n. The research methods are an experimental, cinematically incomplete correlation study of the 3H ( , p ) nn reaction by analyzing measured two-dimensional coincident spectra obtained as a result of eu+ 3H interaction. The projections of the two-dimensional spectra of p-? coincidences with the four-particle reaction 3H (?, p?) nn at an energy of alpha particles of 27.2 MeV (0 Ex 3.5 MeV) on the energy axis of alpha particles for six pairs of cores are analyzed. The Monte Carlo parametrization results show that in the case of the first excited state, 6He in the case of decay only in the limited phase space domain is dominated by the configuration of "alpha particle + di neutron", while with other kinematics and for the second and third excited states, the configurations of "alpha- particle + di neutron "and" alpha particle + cigar "in different ratios. In the case of the first excited state, 6He in the case of decay only in the limited phase space section is dominated by the configuration of the "alpha particle + di neutron," while in the other kinematics and for the second and third excited states, the configurations "alpha particle + " di neutron " and "alpha particle + cigar "in different proportions. The ratio of the configurations is not a constant value for the excited states of the nucleus, but is a dynamic value, which depends on the kinematic conditions of the formation of the 6He nucleus. Product Description popup.authors Горпинич Ольга Костянтинівна Карлишев Юрій Якович Рознюк Юрій Сергійович popup.nrat_date 2020-04-02 Close