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arXiv · 1001.3965

Spin-flip M1 giant resonance as a challenge for Skyrme forces

V. O. Nesterenko·J. Kvasil·P. Vesely·W. Kleinig·P. -G. Reinhard·V. Yu. Ponomarev
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Abstract

Despite a great success of the Skyrme mean-field approach in exploration of nuclear dynamics, it seems to fail in description of the spin-flip M1 giant resonance. The results for different Skyrme parameterizations are contradictory and poorly agree with experiment. In particular, there is no parameterization which simultaneously describes the one-peak gross structure of M1 strength in doubly magic nuclei and two-peak structure in heavy deformed nuclei. The reason of this mismatch could lie in an unsatisfactory treatment of spin correlations and spin-orbit interaction. We discuss the present status of the problem and possible ways of its solution. In particular, we inspect i) the interplay of the collective shift and spin-orbit splitting, ii) the isovector M1 response versus isospin-mixed responses, and iii) the role of tensor and isovector spin-orbit interaction.

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V. O. Nesterenko, J. Kvasil, P. Vesely, W. Kleinig, P. -G. Reinhard, V. Yu. Ponomarev. 2010-01-22. Spin-flip M1 giant resonance as a challenge for Skyrme forces. https://doi.org/10.1088/0954-3899%2F37%2F6%2F064034

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