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Nucleon-nucleon effective potential in dense matter including rho-meson exchange

L. Mornas·E. Gallego·A. Perez
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Abstract

We obtain the RPA summed one-meson exchange potential between nucleons in symmetric nuclear matter at zero temperature, from a model which includes $ρ$, $σ$, $ω$ and $π$ mesons. The behavior of rho mesons inside the medium is first discussed using different schemes to extract a finite contribution from the vacuum polarization. These schemes give qualitatively different results for the in-medium rho mass. The results are discussed in connection with the non-renormalizability of the model. We next study the modified potential as density increases. In the intermediate distance range, it is qualitatively modified by matter and vacuum effects. In the long-distance range ($r>2$ fm), one observes the presence of oscillations, which are not present in free-space. Features on this distance range are insensitive to the renormalization scheme.

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L. Mornas, E. Gallego, A. Perez. 2001-03-14. Nucleon-nucleon effective potential in dense matter including rho-meson exchange. https://arxiv.org/abs/nucl-th/9806093

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