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arXiv · 2508.15426

Algebraic description of the triaxially to axially rotational shape phase transition

Yu Zhang·Yu Xin Liu·Feng Pan·J. P. Draayer
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Abstract

Within the framework of the interacting boson model, we propose a novel algebraic scheme to describe spin-dependent structural evolutions in triaxial nuclei. Our analysis demonstrates that a triaxially to axially rotational shape phase transition can be induced by the high-order correction which is microscopically motivated by the pairing interaction on the $\gamma$-unstable rotation. This prescription is further applied to describe the structural evolutions along the yrast sequences of $^{132}$Ba and $^{130}$Xe, providing an exemplary case for demonstrating a unified explanation of both low-energy collective structures and high-spin phenomena in O(6)-like nuclei.

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Yu Zhang, Yu Xin Liu, Feng Pan, J. P. Draayer. 2025-08-21. Algebraic description of the triaxially to axially rotational shape phase transition. https://doi.org/10.1103/physrevc.111.054303

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