Spectral change of sigma and omega mesons in a dense nuclear medium

Abstract

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.