Spectral change of σ and ω mesons in a dense nuclear medium

The spectra of the scalar (σ) and vector (ω) mesons in nuclear matter are studied in detail using the quark-meson coupling (QMC) model. It is shown that above normal nuclear matter density the effects of σ-ω mixing and the decay of the σ into 2π change the spectra of σ and ω mesons considerably. As in Quantum Hadrodynamics we find a remarkable spectral change in the σ meson and the longitudinal mode of the ω meson, namely a two-peak structure.