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Three-alpha-cluster structure of the 0^+ states in ^{12}C and the effective alpha-alpha interactions

S. I. Fedotov·O. I. Kartavtsev·V. I. Kochkin·A. V. Malykh
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Abstract

The $0^{+}$ states of $^{12}\mathrm{C}$ are considered within the framework of the microscopic three-$α$-cluster model. The main attention is paid to accurate calculation of the width of the extremely narrow near-threshold $0^+_2$ state which plays a key role in stellar nucleosynthesis. It is shown that the $0^{+}_2$-state decays by means of the sequential mechanism ${^{12}\mathrm{C}} \to α+{^8\mathrm{Be}} \to 3α$. Calculations are performed for a number of effective $α- α$ potentials which are chosen to reproduce both energy and width of $^8\mathrm{Be}$. The parameters of the additional three-body potential are chosen to fix both the ground and excited state energies at the experimental values. The dependence of the width on the parameters of the effective $α- α$ potential is studied in order to impose restrictions on the potentials.

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S. I. Fedotov, O. I. Kartavtsev, V. I. Kochkin, A. V. Malykh. 2004-06-02. Three-alpha-cluster structure of the 0^+ states in ^{12}C and the effective alpha-alpha interactions. https://doi.org/10.1103/physrevc.70.014006

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