$\pi \omega \rho$ vertex in nuclear matter

Abstract

Medium modifications of the $\pi \omega \rho$ vertex are analyzed in context of the $\omega \to {\pi }^0{\gamma }^{\ast }$ and $\rho \to \pi {\gamma }^{\ast }$ decays in nuclear matter. A relativistic hadronic model with mesons, nucleons, and $\Delta (1232)$ isobars is applied. A substantial increase of the widths for the decays $\omega \to {\pi }^0{\gamma }^{\ast }$ and $\rho \to \pi {\gamma }^{\ast }$ is found for photon virtualities in the range $0.3-0.6$GeV. This enhancement has a direct importance for the description of dilepton yields from dalitz decays in relativistic heavy-ion collisions.

Comments: 3 pages, 2 Postscript figures, uses appolb.cls (included). Presented at 7th International Workshop on Meson Production, Properties and Interaction, Kraków, Poland, 24-28 May 2002