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Simple approximation for the starting-energy-independent two-body effective interaction with applications to 6Li

D. C. Zheng·B. R. Barrett·J. P. Vary·R. J. McCarthy
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Abstract

We apply the Lee-Suzuki iteration method to calculate the linked-folded diagram series for a new Nijmegen local NN potential. We obtain an exact starting-energy-independent effective two-body interaction for a multi-shell, no-core, harmonic-oscillator model space. It is found that the resulting effective-interaction matrix elements can be well approximated by the Brueckner G-matrix elements evaluated at starting energies selected in a simple way. These starting energies are closely related to the energies of the initial two-particle states in the ladder diagrams. The ``exact'' and approximate effective interactions are used to calculate the energy spectrum of 6Li in order to test the utility of the approximate form.

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D. C. Zheng, B. R. Barrett, J. P. Vary, R. J. McCarthy. 1993-11-24. Simple approximation for the starting-energy-independent two-body effective interaction with applications to 6Li. https://doi.org/10.1103/physrevc.49.1999

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