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Dropping Sigma-Meson Mass and In-Medium S-Wave pion-pion Correlations

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

The influence of a dropping sigma-meson mass on previously calculated in-medium pion-pion correlations in the J=I=0 (sigma-meson) channel is investigated. It is found that the invariant-mass distribution around the vacuum threshold experiences a further strong enhancement with respect to standard many-body effects. The relevance of this result for the explanation of recent $A(π,2π)X$ data is pointed out.

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Z. Aouissat, G. Chanfray, P. Schuck, J. Wambach. 1999-08-31. Dropping Sigma-Meson Mass and In-Medium S-Wave pion-pion Correlations. https://doi.org/10.1103/physrevc.61.012202

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