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arXiv · 2308.02099

The evolution of the chiral symmetry in cesium isotopes

Duo Chen·Jian Li·Rui Guo
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Abstract

Following the reports of candidate chiral doublet bands observed in cesium isotopes, the possible chiral candidates and the evolution of three-dimensional rotation in $^{120-134}{\textrm{Cs}}$ are investigated within the microscopic three-dimensional tilted axis cranking covariant density functional theory (3DTAC-CDFT). By investigating the evolution of the polar angle $\theta$ and azimuth angle $\varphi$ as a function of rotational frequency $\hbar\omega$, the transition from the planar rotation to the chiral rotation has been found in $^{121-133}{\textrm{Cs}}$. The corresponding critical rotational frequency $\omega_{\textrm{crit}}$ of the appearance of chiral aplanar rotation decreases as neutron number increases, which can be attributed to the neutrons in $(gd)$ and $(sd)$ shells having smaller angular momentum components along both the short and long axes, and larger components along medium axis, respectively. In comparison, only planar rotation has been obtained in $^{120,134}{\textrm{Cs}}$. With these interpretations, the obtained $I\sim\hbar\omega$ and energy spectra as well as $B(M1)/B(E2)$ values show reasonable agreement with the available experimental data. In addition, the evolution of quadrupole deformation $\beta$ and triaxial deformation $\gamma$ are also discussed.

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Duo Chen, Jian Li, Rui Guo. 2023-08-04. The evolution of the chiral symmetry in cesium isotopes. https://doi.org/10.1140/epja/s10050-023-01059-8

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