Omega meson propagation in dense nuclear matter and collective excitations

Abstract

The bosonic excitations induced by the omega meson propagation in dense nuclear matter is studied within the framework of random phase approximation. The collective modes are then analyzed by finding the zeros of the relevant dielectric functions. Subsequently we present closed form analytical expressions for the dispersion relations in different kinematical regime. Next, the analytical behaviour of the in-medium effective propagator for the omega meson is examined. This is exploited to calculate the full spectral function for the transverse (T) and longitudinal (L) mode of the omega meson. In addition, various sum rules are constructed for the omega meson spectral density in nuclear medium. Results are then discussed by calculating residues at the poles and discontinuities across the cuts.