Electromagnetic transition strengths in Dy156
Electromagnetic transition strengths in Dy156
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Dy156 的电磁转变强度
DOI：
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
R. Casten
中科院分区：
文献类型：
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作者：
O. Möller;A. Dewald;P. Petkov;B. Saha;A. Fitzler;K. Jessen;D. Tonev;T. Klug;S. Heinze;J. Jolie;P. Brentano;D. Bazzacco;C. Ur;E. Farnea;M. Axiotis;S. Lunardi;G. Angelis;D. Napoli;N. Mărginean;Anthony Martinez;M. Caprio;R. Casten
在符合模式下，用反冲距离多普勒频移技术测量了{sup 156}Dy激发态可靠而精确的寿命。实验是在实验室用GAP阵列和科隆符合柱塞装置进行的，反应{sup124}锡({sup36}S，4N){sup156}Dy，束流能量155 MeV。导出了第一激发带能级布居减少的跃迁分支比的新值。测量的{sup 156}Dy在基态带和第一激发带的跃迁几率以及能谱与最近提出的X(5)模型的预测和相互作用玻色子近似拟合进行了比较。比较发现了带内跃迁强度的不同行为，并表明正常形变的基态带和类X(5)的第一激发带可能共存。它还表明，在{sup 156}Dy中，{Gamma}自由度比在N=90的成熟X(5)核中起到更重要的作用。用一般集体模型对数据的拟合表明，更深的集体势V({β}，{伽马})也可能是导致{sup 156}Dy和那些核的光谱性质不同的一个原因。
Reliable and precise lifetimes of excited states in {sup 156}Dy were measured by means of the recoil distance Doppler-shift technique in the coincidence mode. The experiment was performed at the Laboratori Nazionali di Legnaro with the GASP array and the Cologne coincidence plunger apparatus using the reaction {sup 124}Sn({sup 36}S,4n){sup 156}Dy at a beam energy of 155 MeV. New values of the branching ratios of transitions depopulating the levels of the first excited band have been derived. The measured transition probabilities of {sup 156}Dy in the ground-state band and the first excited band as well as the energy spectra are compared to the predictions of the recently proposed X(5) model and to an interacting boson approximation fit. The comparison reveals a different behavior of the intraband transition strengths and indicates a possible coexistence of a normal deformed ground-state band and an X(5)-like first excited band. It also reveals that in {sup 156}Dy, the {gamma} degree of freedom plays a more important role than it does in the well-established X(5) nuclei with N=90. A fit of the data using the general collective model suggests that a deeper collective potential V({beta},{gamma}) may also be a reason for the differences in the spectroscopicmore » properties of {sup 156}Dy and those nuclei.« less