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arXiv · nucl-th/0505026

Description of intermediate- and short-range NN nuclear force within a covariant effective field theory

Abstract

The present paper is aimed to developing an effective field theory in the GeV region to describe consistently both elastic and inelastic NN-scattering in a fully covariant way. In this development we employ our novel s-channel mechanism of NN-interaction at intermediate and short ranges assuming a formation of the six-quark bag dressed with basic meson fields such as $π$, $σ$, $ρ$ and $ω$ in the intermediate state. The peripheral part of the interaction is governed by t-channel one- and two-pion exchanges described fairly well by chiral perturbation theory. The $σ$-meson dressing should be especially important for the stabilization of the bag due to a high coupling constant of the $σ$-meson with the bag and also a strong interaction between the $σ$-field and space symmetric quark core $|s^6[6]>$. This stabilization of the intermediate dressed bag (which shifts the mass of the bag downward to NN threshold) will be crucially important for the description of $π$, $2π$, $ρ$ and $ω$-meson production in NN-collisions, and, in particular, for the correct description of $π^0$ production near threshold. So that, we expect that the results of the present work will lead to a deeper understanding the short- and intermediate-range nuclear forces and internucleon correlations in nuclei.

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BibTeXRIS

Amand Faessler, V. I. Kukulin, M. A. Shikhalev. 2005-05-10. Description of intermediate- and short-range NN nuclear force within a covariant effective field theory. https://doi.org/10.1016/j.aop.2005.05.008

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