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Generic Rotation in a Collective SD Nucleon-Pair Subspace

Y. M. Zhao·S. Pittel·R. Bijker·A. Frank·A. Arima
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Abstract

Low-lying collective states involving many nucleons interacting by a random ensemble of two-body interactions (TBRE) are investigated in a collective SD-pair subspace, with the collective pairs defined dynamically from the two-nucleon system. It is found that in this truncated pair subspace collective vibrations arise naturally for a general TBRE hamiltonian whereas collective rotations do not. A hamiltonian restricted to include only a few randomly generated separable terms is able to produce collective rotational behavior, as long as it includes a reasonably strong quadrupole-quadrupole component. Similar results arise in the full shell model space. These results suggest that the structure of the hamiltonian is key to producing generic collective rotation.

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Y. M. Zhao, S. Pittel, R. Bijker, A. Frank, A. Arima. 2002-06-18. Generic Rotation in a Collective SD Nucleon-Pair Subspace. https://doi.org/10.1103/physrevc.66.041301

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