Total and Differential Cross-Sections of 16O(γ,n)3Heα8Be0 Reaction

  • S. M. Afanasiev National Science Center Kharkiv Institute of Physics and Technology (1, Akademichna Str., Kharkiv 61108, Ukraine)
Keywords: Photonuclear reactions, Ground state of 8 Be nucleus, Total and differential cross- sections


The 16O(g,n)3He3a-reaction was investigated with the aid of the diffusion camera placed in the magnetic field and irradiated with a beam of bremsstrahlung g-quanta with an endpoint energy of 150 MeV. In to the curve of excitation of the system of 2a‑particles the resonance, identified as the ground state of the nucleus 8Be, were observed. The partial channels of production of these state (16O(g,n)3Hea8Ве0) were isolated and kinematical parameters of g-quantum and neutron were calculated. The absolute total cross-section of the partial channels in the energy interval from the threshold up to 120 MeV was measured. It has been established that the reaction is of a successive type: at first, the neutron is knocked out, and the residual nucleus 15О is in the excited state. The differential cross sections 16O(g,n)3Hea8Ве0-reaction has been measured and the dependence of the asymmetry coefficient distributions of the g-quantum energy and the excitation energy of the compound nucleus at the first intermediate stage of decomposition. The results are explained by the quantum interaction with a quasideuterons model.


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How to Cite
Afanasiev, S. (2018). Total and Differential Cross-Sections of 16O(γ,n)3Heα8Be0 Reaction. Ukrainian Journal of Physics, 63(1), 3-10.
Fields and elementary particles