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S-Wave Pion-Pion Correlations in Dense Nuclear Matter

Z. Aouissat·R. Rapp·G. Chanfray·P. Schuck·J. Wambach
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Abstract

The s-wave correlated $π$-$π$ strength distribution in cold nuclear matter is investigated. The in-medium single pions are renormalized by means of the usual p-wave couplings to nucleons and $Δ$'s. Two groups of models for the $π$-$π$ interaction are studied. The first one uses phenomenological models which reproduce the phase shifts but do not respect the soft-pion theorems. With increasing density a strong accumulation of strength in the subhreshold region is observed. Slightly above saturation density there even occurs an instability with respect to s-wave $π$-$π$ pair condensation. These effects are strongly moderated or disappear altogether if constraints from chiral symmetry are built into the $π$-$π$ interaction.

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Z. Aouissat, R. Rapp, G. Chanfray, P. Schuck, J. Wambach. 1994-06-09. S-Wave Pion-Pion Correlations in Dense Nuclear Matter. https://doi.org/10.1016/0375-9474(94)00429-q

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