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RPA approach to rotational symmetry restoration in a three-level Lipkin model

K. Hagino·G. F. Bertsch
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Abstract

We study an extended Lipkin-Meshkov-Glick model that permits a transition to a deformed phase with a broken continuous symmetry. Unlike simpler models, one sees a persistent zero-frequency Goldstone mode past the transition point into the deformed phase. We found that the RPA formula for the correlation energy provides a useful correction to the Hartree-Fock energy when the number of particle N satisfies N > 3, and becomes accurate for large N. We conclude that the RPA correlation energy formula offers a promising way to improve the Hartree-Fock energy in a systematic theory of nuclear binding energies.

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K. Hagino, G. F. Bertsch. 1999-09-10. RPA approach to rotational symmetry restoration in a three-level Lipkin model. https://doi.org/10.1103/physrevc.61.024307

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