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Energy shifted level densities in the rare earth region

M. Guttormsen·M. Hjorth-Jensen·E. Melby·J. Rekstad·A. Schiller·S. Siem
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Abstract

The density of accessible levels at low spin in the (3-He,alpha gamma) reaction has been extracted for the 161,162-Dy and 171,172-Yb nuclei. The energy shift between the level densities of the even-odd and even-even isotopes is measured as a function of excitation energy. The results are compared with predictions from various semi-empirical models. The energy shift procedure works well for excitation energies between 3.5 and 7 MeV in the even-even nucleus, provided that a proper level density function is used. The experimental energy shift is close to the pairing gap parameter Delta.

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M. Guttormsen, M. Hjorth-Jensen, E. Melby, J. Rekstad, A. Schiller, S. Siem. 2000-01-27. Energy shifted level densities in the rare earth region. https://doi.org/10.1103/physrevc.61.067302

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