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arXiv · 2111.13437

Effects of rotation and valence nucleons in molecular-like $α$-chain nuclei

D. D. Zhang·Z. X. Ren·P. W. Zhao·D. Vretenar·T. Nikšić·J. Meng
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Abstract

Effects of rotation and valence nucleons in molecular-like linear $α$-chain nuclei are analyzed using a three-dimensional lattice cranking model based on covariant density functional theory. The structure of $^{16}$C and $^{16}$Ne is investigated as a function of rotational frequency. The valence nucleons, with respect to the 3$α$ linear chain core of $^{12}$C, at low frequency occupy the $π$ molecular orbital. With increasing rotational frequency these nucleons transition from the $π$ orbital to the $σ$ molecular orbital, thus stabilizing the 3$α$ linear chain structure. It is predicted that the valence protons in $^{16}$Ne change occupation from the $π$ to the $σ$ molecular orbital at $\hbarω\approx 1.3$ MeV, a lower rotational frequency compared to $\hbarω\approx 1.7$ MeV for the valence neutrons in $^{16}$C. The same effects of valence protons are found in $^{20}$Mg, compared to the four valence neutrons in $^{20}$O. The model is also used to examine the effect of alignment of valence nucleons on the relative positions and size of the three $α$-clusters in $^{16}$C and $^{16}$Ne.

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D. D. Zhang, Z. X. Ren, P. W. Zhao, D. Vretenar, T. Nikšić, J. Meng. 2023-10-04. Effects of rotation and valence nucleons in molecular-like $α$-chain nuclei. https://doi.org/10.1103/physrevc.105.024322

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