Dispersion relations of mesons in symmetric nuclear matter
Abstract
Description
We calculate dispersion relations and propagators for the $σ$, $ω$, $π$, $ρ$, $δ$, $η$ and $a_1$ mesons in relativistic, dense, hot, symmetric nuclear matter. In addition to the usual mixing of the $σ-ω$ system, we obtain mixing of the $δ$ with the longitudinal $ρ$ mode and of the tranverse $ρ$ with the transverse $a_1$ mode. Finally, the component of the $a_1$ polarization along the transferred momentum modifies the in-medium pion propagator in a way similar to the Migdal contact interaction, but with the opposite sign. The spurious pion condensate as well as the additional contribution from the $a_1$ meson are removed by a contact term. We compare two ways of implementing contact term subtraction.
35 pages, 10 figures, subm. to J. Phys. G
35 pages, 10 figures, subm. to J. Phys. G