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Ab initio shell model with a genuine three-nucleon force for the p-shell nuclei

P. Navratil·W. E. Ormand
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Abstract

The ab initio no-core shell model (NCSM) is extended to include a realistic three-body interaction in calculations for p-shell nuclei. The NCSM formalism is reviewed and new features needed in calculations with three-body forces are discussed in detail. We present results of first applications to 6,7Li, 6He, 7,8,10Be, 10,11,12B, 12N and 10,11,12,13C using the Argonne V8' nucleon-nucleon (NN) potential and the Tucson-Melbourne TM'(99) three-nucleon interaction (TNI). In addition to increasing the total binding energy, we observe a substantial sensitivity in the low-lying spectra to the presence of the realistic three-body force and an overall improvement in the level-ordering and level-spacing in comparison to experiment. The greatest sensitivity occurs for states where the spin-orbit interaction strength is known to play a role. In particular, with the TNI we obtain the correct ground-state spin for 10,11,12B and 12N, contrary to calculations with NN potentials only.

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P. Navratil, W. E. Ormand. 2003-05-29. Ab initio shell model with a genuine three-nucleon force for the p-shell nuclei. https://doi.org/10.1103/physrevc.68.034305

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