The work is focused on investigation of properties of exotic light nuclei. The studied 6Be and 10He nuclei populated in the p(6Li,6Be)n charge-exchange reaction and in the 3H(8He,p)10He two-neutron transfer reaction, respectively, represent attractive examples of proton- and neutron-rich three-cluster systems.
An adequate approach to treat complicated spectra formed by broad overlapping resonances has been found. To analyse the experimental data and to perform the simulations, the SIMONE software framework has been developed. It is a general instrument which may be employed for a wide range of studies typical for the field of low-energy nuclear physics. SIMONE is based on ROOT Data Analysis Framework and it takes the advantages of GEANT4 and SRIM.
Population of the three-body α+p+p continuum states in 6Be has been investigated up to 16 MeV above its three-body decay threshold. The 0+ ground state and the 2+ first excited state has been observed at 1.37 MeV and at 3.05 MeV, respectively, above the three-body decay threshold. Moreover, a broad structure extending from 4 to 16 MeV has been observed. It contains negative parity states populated by ∆L = 1 angular momentum transfer. This structure has been interpreted as reveal of the isovector soft dipole mode of excitation and it has been demonstrated that it is a dominant component of the 6Be spectrum populated in the charge-exchange reaction. Theoretical model describing population of 6Be 0+ and 2+ states in the charge-exchange (p,n) reaction and the following three-body α+p+p decay of 6Be has been developed. High statistics of experimental data has allowed to carry out detailed correlation analysis of the 0+ and 2+ states.
The 10He ground state has been observed in the missing mass spectrum at the energy of 2.1 MeV above the three-body 8He+n+n decay threshold. Analysis of the angular correlations of the 10He decay products has allowed to interpret obtained spectrum as a coherent superposition of a broad 1− state having a maximum at energy 4-6 MeV and a 2+ state above 6 MeV.