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arXiv · 1206.3399

Observation of large scissors resonance strength in actinides

M. Guttormsen·L. A. Bernstein·A. Bürger·A. Görgen·F. Gunsing·T. W. Hagen·A. C. Larsen·T. Renstrøm·S. Siem·M. Wiedeking·J. N. Wilson
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Abstract

The orbital M1-scissors resonance (SR) has been measured for the first time in the quasi-continuum of actinides. Particle-gamma coincidences are recorded with deuteron and 3He induced reactions on 232Th. The residual nuclei 231,232,233Th and 232,233Pa show an unexpectedly strong integrated strength of $B_{M1} = 11-15 μ_{n}^{2}$ in the Egamma=1.0 - 3.5 MeV region. The increased gamma-decay probability in actinides due to the SR is important for cross-section calculations for future fuel cycles of fast nuclear reactors and may also have impact on stellar nucleosynthesis.

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M. Guttormsen, L. A. Bernstein, A. Bürger, A. Görgen, F. Gunsing, T. W. Hagen, A. C. Larsen, T. Renstrøm, S. Siem, M. Wiedeking, J. N. Wilson. 2012-06-15. Observation of large scissors resonance strength in actinides. https://doi.org/10.1103/physrevlett.109.162503

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