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A Shell Model Description of the Decay Out of the Super-Deformed Band of 36Ar

E. Caurier·F. Nowacki·A. Poves
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Abstract

Large scale shell model calculations in two major oscillator shells (sd and pf) describe simultaneously the super-deformed excited band of 36Ar and its low-lying states of dominant sd character. In addition, several two particle two hole states and a side band of negative parity are also well reproduced. We explain the appearance of the super-deformed band at such low excitation energy as a consequence of the very large correlation energy of the configurations with many particles and many holes (np-nh) relative to the normal filling of the spherical mean field orbits (0p-0h). We study the mechanism of mixing between these different configurations, to understand why the super-deformed band survives and how it finally decays into the low-lying sd-dominated states via the indirect mixing of the 0p-0h and 4p-4h configurations.

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E. Caurier, F. Nowacki, A. Poves. 2005-05-19. A Shell Model Description of the Decay Out of the Super-Deformed Band of 36Ar. https://doi.org/10.1103/physrevlett.95.042502

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