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