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ESC NN-Potentials in Momentum Space. II. Meson-Pair Exchange Potentials

Th. A. Rijken·H. Polinder·J. Nagata
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Abstract

The partial wave projection of the Nijmegen soft-core potential model for Meson-Pair-Exchange (MPE) for NN-scattering in momentum space is presented. Here, nucleon-nucleon momentum space MPE-potentials are NN-interactions where either one or both nucleons contains a meson-pair vertex. Dynamically, the meson-pair vertices can be viewed as describing in an effective way (part of) the effects of heavy-meson exchange and meson-nucleon resonances. From the point of view of ``duality,'' these two kinds of contribution are roughly equivalent. Part of the MPE-vertices can be found in the chiral-invariant phenomenological Lagrangians that have a basis in spontaneous broken chiral symmetry. It is shown that the MPE-interactions are a very important component of the nuclear force, which indeed enables a very succesful description of the low and medium energy NN-data. Here we present a precise fit to the NN-data with the extended-soft-core (ESC) model containing OBE-, PS-PS-, and MPE-potentials. An excellent description of the NN-data for $T_{Lab} \leq 350$ MeV is presented and discussed. Phase shifts are given and a $χ^2_{p.d.p.} = 1.15$ is reached.

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Th. A. Rijken, H. Polinder, J. Nagata. 2002-01-08. ESC NN-Potentials in Momentum Space. II. Meson-Pair Exchange Potentials. https://doi.org/10.1103/physrevc.66.044009

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