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arXiv · 2005.10143

Exact sum rules with approximate ground states

Calvin W. Johnson·Ken A. Luu·Yi Lu
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Abstract

Electromagnetic and weak transitions tell us a great deal about the structure of atomic nuclei. Yet modeling transitions can be difficult: it is often easier to compute the ground state, if only as an approximation, than excited states. One alternative is through transition sum rules, in particular the non-energy-weighted and energy-weighted sum rules, which can be computed as expectation values of operators. We investigate by computing sum rules for a variety of nuclei, comparing the numerically exact full configuration-interaction shell model, as a reference, to Hartree-Fock, projected Hartree-Fock, and the nucleon pair approximation. These approximations yield reasonable agreement, which we explain by prior work on the systematics of transition moments.

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Calvin W. Johnson, Ken A. Luu, Yi Lu. 2020-09-18. Exact sum rules with approximate ground states. https://doi.org/10.1088/1361-6471%2Fabacda

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