Spectroscopy of a tetrahedral doubly magic candidate nucleus 160 70 Yb 90
Journal of Physics G(2019)
摘要
The decay scheme of $^{160}$Yb nucleus populated in the $^{148}$Sm($^{16}$O, 4n)$^{160}$Yb reaction at 90 MeV has been studied. The gamma-coincidence data have been collected by using Indian National Gamma Array (INGA) composed of twenty Compton-suppressed Clover-Germanium detectors. Compared to the prior publications, the level scheme has been significantly modified owing to the observation of triple $\gamma$-coincidences and the measurements of $\gamma$ intensities, R$_{\theta}$ (asymmetry ratio), DCO (Directional Correlation of Oriented States) and IPDCO (Integrated Polarisation Directional Correlation of Oriented States) ratios. Theoretical results relevant for the exotic shape-coexistence related to the present context are presented and discussed. They illustrate the consequences of the fact that $^{160}$Yb is expected to be a doubly-magic (Z=70 and N=90) tetrahedral-symmetry nucleus as predicted by other authors. The historical criteria of identification of such a symmetry in nuclei are critically revisited in the context of the actual measurement and interpretation of its results and the precise new criteria are formulated employing recent results of the Fukuoka-Strasbourg collaboration. The experimental results are interpreted and discussed in detail. Limiting values of branching ratios for transitions observed by other authors but unseen in the present work are estimated. The population criteria of the $\beta$ and $\gamma$ vibration bands are revisited and discussed. Although no indication of the presence of the stable tetrahedral configuration has been obtained, arguments are given towards the possible presence of the $Y_{32}$ (`tetrahedral component') vibrations around the ground-state equilibrium. With the improvement of the spectroscopic information provided by the new data the way is opened for designed experiment(s) based on the unambiguous identification criteria of tetrahedral symmetry presented in this article.
更多查看译文
关键词
nucleus,doubly
AI 理解论文
溯源树
样例
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要