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arXiv · 2511.15040

Exploring highly-deformed ground states involving the second intruder orbit in Z>50 even-even nuclei

Tsunenori Inakura·Wataru Horiuchi·Shin'ichiro Michimasa·Masaomi Tanaka
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Abstract

We present a systematic survey of even-even nuclei with $Z>50$ to identify where a very large prolate configuration driven by the second intruder orbit emerges. Within the energy density functional theory framework, we find in representative cases a pronounced prolate minimum at quadrupole deformation $\beta_2\approx$ 0.3--0.4. A characteristic feature of these minima is a local enhancement of the hexadecapole ($\beta_4$) component relative to nearby deformations, which is a clear fingerprint of the $\beta_2$--$\beta_4$ coupling expected for the second intruder orbit. Representative comparisons among three Skyrme interactions show a similar appearance of the highly deformed minimum and a local enhancement of $\beta_4$ at the prolate minimum, indicating qualitative robustness with respect to the interaction. The resulting maps highlight specific heavy nuclei where highly deformed ground states are anticipated.

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Tsunenori Inakura, Wataru Horiuchi, Shin'ichiro Michimasa, Masaomi Tanaka. 2025-11-19. Exploring highly-deformed ground states involving the second intruder orbit in Z>50 even-even nuclei. https://arxiv.org/abs/2511.15040

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