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arXiv · 2505.07288

Large quadrupole moment in $^{20}$Ne:Localization and tensor-force effects

Xue Huai-Tong·Qiu Suo·Chen C. F.·Chen Q. B.·Zhou Xian-Rong·Ren Zhongzhou
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Abstract

Using the Beyond-Skyrme-Hartree-Fock approach with various Skyrme-type $NN$ effective interactions, we explore the large spectroscopic quadrupole moment $Q_s$ of the first excited $2_{1}^{+}$ state in $^{20}$Ne. Our calculated $Q_s(2_{1}^{+}) \approx -0.20~e\textrm{b}$ aligns closely with the experimental value of $-0.22(2)~e\textrm{b}$. Consistent with other theoretical methods, our results confirm the presence of an $\alpha$ cluster structure in this state. We also investigate the robustness of the $\alpha$ cluster against tensor-force, demonstrating that incorporating tensor components significantly enhances $Q_s(2_{1}^{+})$ and strengthens the cluster structure along the symmetrical axis.

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Xue Huai-Tong, Qiu Suo, Chen C. F., Chen Q. B., Zhou Xian-Rong, Ren Zhongzhou. 2025-05-12. Large quadrupole moment in $^{20}$Ne:Localization and tensor-force effects. https://arxiv.org/abs/2505.07288

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