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arXiv · 2005.03865

Static quadrupole moments of nuclear chiral doublet bands

Q. B. Chen·N. Kaiser·Ulf-G. Meißner·J. Meng
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Abstract

The static quadrupole moments (SQMs) of nuclear chiral doublet bands are investigated for the first time taking the particle-hole configuration $π(1h_{11/2}) \otimes ν(1h_{11/2})^{-1}$ with triaxial deformation parameters in the range $260^\circ \leq γ\leq 270^\circ$ as examples. The behavior of the SQM as a function of spin $I$ is illustrated by analyzing the components of the total angular momentum. It is found that in the region of chiral vibrations the SQMs of doublet bands are strongly varying with $I$, whereas in the region of static chirality the SQMs of doublet bands are almost constant. Hence, the measurement of SQMs provides a new criterion for distinguishing the modes of nuclear chirality. Moreover, in the high-spin region the SQMs can be approximated by an analytic formula with a proportionality to $\cosγ$ for both doublet bands. This provides a way to extract experimentally the triaxial deformation parameter $γ$ for chiral bands from the measured SQMs.

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Q. B. Chen, N. Kaiser, Ulf-G. Meißner, J. Meng. 2020-05-08. Static quadrupole moments of nuclear chiral doublet bands. https://doi.org/10.1016/j.physletb.2020.135568

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