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تسجيل مستخدم جديدOrigin of Low-Lying Enhanced E1 Strength in Rare-Earth Nuclei
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The experimental $E1$ strength distribution below 4 MeV in rare-earth nuclei suggests a local breaking of isospin symmetry. In addition to the octupole states, additional $1^-$ states with enhanced E1 strength have been observed in rare-earth nuclei by means of ($gamma,gamma$) experiments. By reproducing the experimental results, the spdf interacting boson model calculations provide further evidence for the formation of an $alpha$ cluster in medium-mass nuclei and might provide a new understanding of the origin of low-lying E1 strength.
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V.A. Plujko
, O.O. Kavatsyuk (Taras Shevchenko National University;n Institute for Nuclear Research
, Kiev
2002
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