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arXiv · nucl-th/9611019

The Two-Pion Exchange NN-Potential in Nuclear Matter and Nuclear Stability

R. Rapp·J. W. Durso·J. Wambach
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Abstract

A meson exchange model of the $ππ$ interaction which fits free $ππ$ scattering data is used to calculate the interactions of pions in nuclear matter as a function of nuclear density. Polarization of the nuclear medium by the pions results in a marked increase in the s-wave $ππ$ attraction at low energy. The influence of this effect on the nucleon-nucleon interaction is a corresponding increase with density of the $NN$ central potential due to the exchange of two correlated pions, resulting in an $NN$ interaction which fails to saturate. A possible mechanism for restoring the theoretical stability of nuclear matter is explored and found to be effective.

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R. Rapp, J. W. Durso, J. Wambach. 1996-11-11. The Two-Pion Exchange NN-Potential in Nuclear Matter and Nuclear Stability. https://doi.org/10.1016/s0375-9474(96)00482-4

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