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arXiv · 1205.0383

Effective shell-model hamiltonians from realistic nucleon-nucleon potentials within a perturbative approach

L. Coraggio·A. Covello·A. Gargano·N. Itaco·T. T. S. Kuo
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Abstract

This paper discusses the derivation of an effective shell-model hamiltonian starting from a realistic nucleon-nucleon potential by way of perturbation theory. More precisely, we present the state of the art of this approach when the starting point is the perturbative expansion of the Q-box vertex function. Questions arising from diagrammatics, intermediate-states and order-by-order convergences, and their dependence on the chosen nucleon-nucleon potential, are discussed in detail, and the results of numerical applications for the p-shell model space starting from chiral next-to-next-to-next-to-leading order potentials are shown. Moreover, an alternative graphical method to derive the effective hamiltonian, based on the Z-box vertex function recently introduced by Suzuki et al., is applied to the case of a non-degenerate (0+2) hbaromega model space. Finally, our shell-model results are compared with the exact ones obtained from no-core shell-model calculations.

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L. Coraggio, A. Covello, A. Gargano, N. Itaco, T. T. S. Kuo. 2012-05-02. Effective shell-model hamiltonians from realistic nucleon-nucleon potentials within a perturbative approach. https://doi.org/10.1016/j.aop.2012.04.013

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