S-Wave Pion-Pion Correlations in Dense Nuclear Matter
arXiv:nucl-th/9406010 · doi:10.1016/0375-9474(94)00429-Q
Abstract
The s-wave correlated $Ï$-$Ï$ 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 $Î$'s. Two groups of models for the $Ï$-$Ï$ 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 $Ï$-$Ï$ pair condensation. These effects are strongly moderated or disappear altogether if constraints from chiral symmetry are built into the $Ï$-$Ï$ interaction.
22 pages, LATEX, 12 figures (not included, available from the authors), KFA-IKP(TH)-1994-21