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Ab-initio No-Core Shell Model With Many-Body Forces

M. S. Fayache·J. P. Vary·B. R. Barrett·P. Navratil·S. Aroua
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Abstract

Working in the framework of the ab-initio no-core shell model, we derive two-body effective interactions microscopically for specific harmonic-oscillator basis spaces from the realistic Argonne V8' nucleon-nucleon potential. However, our two-body effective interaction is only the dominant part of the A-body (A >= 3) effective interaction, which also contains three-, four- and, in general, up to A-body components. We model these multi-body components as a simple two-parameter, basis-space-dependent interaction. We then investigate the coupling needed to provide accurate descriptions of selected nuclear observables. We successfully model the multi-body interaction as a zero-range two-body operator times the number operator Nsps that measures the harmonic-oscillator quanta of the spectator nucleons.

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M. S. Fayache, J. P. Vary, B. R. Barrett, P. Navratil, S. Aroua. 2001-12-21. Ab-initio No-Core Shell Model With Many-Body Forces. https://arxiv.org/abs/nucl-th/0112066

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