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91.
YANG Yun-Yi ZHU Sheng-Jiang J.H. Hamilton A.V. Ramayya J. K. Hwang J.O. Rasmussen Y.X. Luo K. Li DING Huai-Bo WANG Jian-Guo XU Qiang GU Long 《中国物理C(英文版)》2009,33(Z1)
High-spin states in neutron-rich 102Mo nucleus have been studied by measuring the prompt γ-rays in the spontaneous fission of 252Cf. The previous level scheme has been updated and some new levels and transitions are identified. The one-phonon γ-band is expanded and a band head level of the two-phonon γ-band is proposed. The systematic characteristics of yrast bands, one-phonon γ-bands, two-phonon γ-bands and quasi-particle bands in 102Mo, 104Mo and 106Mo are discussed. 相似文献
92.
ZHU Sheng-jiang DING Huai-bo J.H.Hamilton A.V.Ramayya CHE Xing-lai J.K.Hwang Y.X.Luo J.O.Rasmussen K.Li WANG Jian-guo XU Qiang GU Long YANG Yun-yi S.Frauendorf V.Dimitrov 《原子核物理评论》2009,26(Z1)
The level structures of neutron-rich ~(105)Mo,~(106)Mo,~(108)Mo and 110Ru nuclei in A≈100 region have been carefully investigated by coincidence measurements of the prompt γ-rays populated in the spontaneous fission of ~(252)Cf with the Gammasphere detector array.In 105Mo,one-phonon K =9/2 and two-phonon K=13/2 γ-vibrational bands have been identified.In ~(108)Mo,one-phonon γ-vibrational band is expanded and two-phonon γ-vibrational band has been identified.Two similar sets of bands in ~(106)Mo and ~(110)Ru are observed to high spins,which have been proposed as the soft chiral γ-vibrational bands.The characteristics for these γ-vibrational bands and chiral doublet bands have been discussed. 相似文献
93.
对于发生在同一个原子核中的、从一种高有序激发模式向着另一种低有序激发模式演化的机理和物理图像,提出了一种新的理解:被布居到高角动量态的高有序激发核,以E2跃迁方式先行退耦到yrast带,再退耦到共存区时释放了结构能,诱发价核子对耦合强度改变,重新组合出低有序的激发模式基准态,实现了基准态结构的过渡.从微观上看,这是一种既温和而又平稳的转变.并以76Sr核为例作了深入阐述.
关键词:
量子相变
yrast带结构演化
微观sdIBM-2方案
76Sr核')" href="#">76Sr核 相似文献
94.
95.
The structure of an unexpected compound from the dehydration of an aldol addition product has been determined using 1-D and 2-D NMR techniques. This reaction is the last step in a new synthetic approach to the galanthan ring system. Complete 1H and 13C NMR assignments for two synthetic precursors are also reported. 相似文献
96.
97.
原子核多体系统中可以存在一类被称为α凝聚体的奇异物理态。该奇异态可以被视为玻色-爱因斯坦凝聚在原子核物理中的推广。一般认为,α凝聚体不仅可以存在于12C中,也可以存在于诸如16O,20Ne,24Mg,28Si等质量更重的自共轭原子核中。重自共轭原子核中的α凝聚体的物理性质是核结构理论重要的研究课题,相关理论计算可以为实验研究提供有益参考。主要介绍了该研究方向的基本理论框架,包括Tohsaki-Horiuchi-Schuck-Röpke波函数方法、Yamada-Schuck模型,以及近期提出的半解析近似方法。还讨论了α粒子间四体相互作用对α凝聚体物理性质的影响,并对α凝聚体破裂和一维α凝聚体等可能的研究方向做了简要论述。α condensates are exotic states in nuclear many-body systems, and can be viewed as the generalization of the Bose-Einstein condensate in nuclear physics. It is widely believed that, α condensates exist not only in 12C, but also in heavier self-conjugate nuclei such as 16O, 20Ne, 24Mg, 28Si, etc. It is important to understand the physical properties of these α condensates in heavy self-conjugate nuclei from the theoretical perspective, and the theoretical results could be a useful reference for the experimental studies. This work reviews the basic frameworks to study α condensates, including the Tohsaki-Horiuchi-Schuck-Röpke wave function, the Yamada-Schuck model, and the recently proposed semi-analytic approximation. The impacts of the four-body interactions of α particles on the physical properties of α condensates are reported. The breakup of α condensates and the one-dimensional α condensates are discussed briefly as the possible future directions in this field. 相似文献
98.
Deformed photon-added entangled squeezed vacuum and one-photon states: Entanglement,polarization, and nonclassical properties 下载免费PDF全文
In this paper, after a brief review on the entangled squeezed states, we produce a new class of the continuous-variabletype entangled states, namely, deformed photon-added entangled squeezed states. These states are obtained via the iterated action of the f-deformed creation operator A = f(n)aon the entangled squeezed states. In the continuation, by studying the criteria such as the degree of entanglement, quantum polarization as well as sub-Poissonian photon statistics, the twomode correlation function, one-mode and two-mode squeezing, we investigate the nonclassical behaviors of the introduced states in detail by choosing a particular f-deformation function. It is revealed that the above-mentioned physical properties can be affected and so may be tuned by justifying the excitation number, after choosing a nonlinearity function. Finally, to generate the introduced states, we propose a theoretical scheme using the nonlinear Jaynes–Cummings model. 相似文献
99.
The paper proposes a robust approach to automatic segmentation of leukocyte's nucleus from microscopic blood smear images under normal as well as noisy environment by employing a new exponential intuitionistic fuzzy divergence based thresholding technique. The algorithm minimizes the divergence between the actual image and the ideally thresholded image to search for the final threshold. A new divergence formula based on exponential intuitionistic fuzzy entropy has been proposed. Further, to increase its noise handling capacity, a neighborhood-based membership function for the image pixels has been designed. The proposed scheme has been applied on 110 normal and 54 leukemia (chronic myelogenous leukemia) affected blood samples. The nucleus segmentation results have been validated by three expert hematologists. The algorithm achieves an average segmentation accuracy of 98.52% in noise-free environment. It beats the competitor algorithms in terms of several other metrics. The proposed scheme with neighborhood based membership function outperforms the competitor algorithms in terms of segmentation accuracy under noisy environment. It achieves 93.90% and 94.93% accuracies for Speckle and Gaussian noises, respectively. The average area under the ROC curves comes out to be 0.9514 in noisy conditions, which proves the robustness of the proposed algorithm. 相似文献
100.
The \begin{document}$ \alpha $\end{document} ![]()
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-particle preformation factors of nuclei above doubly magic nuclei \begin{document}$ ^{100} $\end{document} ![]()
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Sn and \begin{document}$ ^{208} $\end{document} ![]()
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Pb are investigated within the generalized liquid drop model. The results show that the \begin{document}$ \alpha $\end{document} ![]()
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-particle preformation factors of nuclei near self-conjugate doubly magic \begin{document}$ ^{100} $\end{document} ![]()
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Sn are significantly larger than those of analogous nuclei just above \begin{document}$ ^{208} $\end{document} ![]()
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Pb, and they will be enhanced as the nuclei move towards the \begin{document}$ N = Z $\end{document} ![]()
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line. The proton–neutron correlation energy \begin{document}$ E_{p-n} $\end{document} ![]()
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and two protons–two neutrons correlation energy \begin{document}$ E_{2p-2n} $\end{document} ![]()
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of nuclei near \begin{document}$ ^{100} $\end{document} ![]()
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Sn also exhibit a similar situation, indicating that the interactions between protons and neutrons occupying similar single-particle orbitals could enhance the \begin{document}$ \alpha $\end{document} ![]()
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-particle preformation factors and result in superallowed \begin{document}$ \alpha $\end{document} ![]()
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decay. This also provides evidence of the significant role of the proton–neutron interaction on \begin{document}$ \alpha $\end{document} ![]()
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-particle preformation. Also, the linear relationship between \begin{document}$ \alpha $\end{document} ![]()
![]()
-particle preformation factors and the product of valence protons and valence neutrons for nuclei around \begin{document}$ ^{208} $\end{document} ![]()
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Pb is broken in the \begin{document}$ ^{100} $\end{document} ![]()
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Sn region because the \begin{document}$ \alpha $\end{document} ![]()
![]()
-particle preformation factor is enhanced when a nucleus near \begin{document}$ ^{100} $\end{document} ![]()
![]()
Sn moves towards the \begin{document}$ N = Z $\end{document} ![]()
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line. Furthermore, the calculated \begin{document}$ \alpha $\end{document} ![]()
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decay half-lives fit well with the experimental data, including the recent observed self-conjugate nuclei \begin{document}$ ^{104} $\end{document} ![]()
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Te and \begin{document}$ ^{108} $\end{document} ![]()
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Xe [Phys. Rev. Lett. 121, 182501 (2018)]. 相似文献