Medium effects on meson couplings and dilepton spectra

Abstract

The pi omega rho coupling constant is calculated in a relativistic hadronic framework incorporating nucleons and Delta(1232) isobars. Medium modifications are included. The vertex is analyzed in context of the omega to pi e+e- and rho to pi e+e- Dalitz decays in nuclear matter. A sizeable increase of the widths for these decays is found for invariant mass of dileptons in the range 0.2-0.5 GeV. This increase may help, among other medium effects, to explain the problem of the low-mass dilepton enhancement seen in relativistic heavy-ion collisions.

8 pages, 8 figures, talk presented at the 3rd Budapest Winter School on Heavy Ion Physics, 8-11 December, 2003, Budapest, Hungary

References in corpus (7)

• Low-Mass Dileptons at the CERN-SpS: Evidence for Chiral Restoration?
• Modifications of the Rho Meson from the Virtual Pion Cloud in Hot and Dense Matter
• Momentum Dependence of the Pion Cloud for Rho Mesons in Nuclear Matter
• Pion electromagnetic form factor at finite temperature
• $\rho (770{)}^0$ and $f_0(980)$ Production in Au+Au and pp Collisions at $\sqrt{s_{NN}}$ = 200 GeV
• rho -> pi pi decay in nuclear medium
• pi^0 -> gamma gamma*, omega -> pi^0 gamma*, and rho -> pi gamma* decays in nuclear medium