Direct reactions involving exotic nuclei He-8 and H-5

The angular distribution of 26 MeV/n He-8 ions elastically scattered from a gaseous helium target was measured in a wide CM angular range. Results are discussed in terms of the potential scattering and neutron transfer. The a ngular distributions of elastic scattering as well as 1n and 2n transfer re actions of these ions on protons are presented. Finite-range DWBA calculati ons made for the 2n transfer reaction leading to the ground (0(+)) and exci ted (2(+)) states of He-6 underestimate the cross section for 2n transfer t o He-6(0(+)). Analysis of data for this reaction channel suggests the impor tance of a direct H-5-cluster exchange process. A resonance state of H-5 wi th an energy of 2 MeV above the decay threshold n + n + H-3 was obtained fo r the first time by making use of the reaction p(He-6, He-2)H-5.