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Medium Modification of The Pion-Pion Interaction at Finite Density

D. Davesne·Y. J. Zhang·G. Chanfray
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Abstract

We discuss medium modifications of the unitarized pion-pion interaction in the nuclear medium. We incorporate both the effects of chiral symmetry restoration and the influence of collective nuclear pionic modes originating from the p-wave coupling of the pion to delta-hole configurations. We show in particular that the dropping of the sigma meson mass significantly enhances the low energy structure created by the in-medium collective pionic modes.

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D. Davesne, Y. J. Zhang, G. Chanfray. 1999-09-15. Medium Modification of The Pion-Pion Interaction at Finite Density. https://doi.org/10.1103/physrevc.62.024604

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