The Hoyle State of 12C Nucleus in the 14N(γ, np)3α Reaction


  • S.N. Afanasiev National Science Center Kharkiv Institute of Physics and Technology



photonuclear reactions, 4, ground state of 8Be nucleus, Hoyle state of 12C nucleus


The distributions over the excitation energies of the systems of two and three α-particles in the 14N(γ, np)3α reaction have been analyzed. In the 2α-particle distribution, a channel of the 8Be nucleus formation in the ground state is revealed and resolved. For the events corresponding to this channel, a distribution of events over the excitation energy of three α-particles is plotted. A maximum is found in the near-threshold 3α-particle region, which can correspond to the Hoyle state of 12C nucleus. Events corresponding to the partial channel of the 14N(γ, np)12C*(0+) reaction with the subsequent two-particle decay 12C* → α + 8Be(0+) are separated, and the energy and angular distributions of α-particles at each decay stage are analyzed. The channel of 12C nucleus formation in the Hoyle state in photonuclear reactions has not been identified earlier.


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How to Cite

Afanasiev, S. (2023). The Hoyle State of 12C Nucleus in the 14N(γ, np)3α Reaction. Ukrainian Journal of Physics, 67(11), 776.



Fields and elementary particles