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arXiv · 0803.2564

Towards an Extended Microscopic Theory for the Upper fp-shell nuclei

K. P. Drumev·C. Bahri·J. P. Draayer·V. G. Gueorguiev
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Abstract

An extended SU(3) shell model that for the first time explicitly includes unique-parity levels is introduced. Shell-model calculations for the isotopes of $^{64}$Ge and $^{68}$Se are performed where valence nucleons beyond the N=28=Z core occupy levels of the normal parity upper-$fp$ shell ($f_{5/2},p_{3/2},p_{1/2}$) and the unique parity $g_{9/2}$ intruder configuration. The levels of the upper-$fp$ shell are handled within the framework of an m-scheme basis as well as its pseudo-SU(3) counterpart, and respectively, the $g_{9/2}$ as a single level and as a member for the complete $gds$ shell. It is demonstrated that the extended SU(3) approach allows one to better probe the effects of deformation and to account for many key properties of the system by using a highly truncated model space.

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K. P. Drumev, C. Bahri, J. P. Draayer, V. G. Gueorguiev. 2008-03-18. Towards an Extended Microscopic Theory for the Upper fp-shell nuclei. https://doi.org/10.1142/9789812833433_0006

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