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In-medium Pion-Pion Interaction and Chiral Symmetry Restoration

D. Davesne·Y. J. Zhang·G. Chanfray·J. Wambach
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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 how the resulting strong enhancement of the sigma-meson spectral function is related to large fluctuations of the condensate associated with the partial restoration of chiral symmetry.

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D. Davesne, Y. J. Zhang, G. Chanfray, J. Wambach. 2000-02-11. In-medium Pion-Pion Interaction and Chiral Symmetry Restoration. https://arxiv.org/abs/nucl-th/0002032

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