VECTOR DOMINANCE MODEL AT FINITE TEMPERATURE

The neutral rho-meson propagator is computed at finite temperature using standard pi-rho dynamics. The vector dominance model states that the hadronic electromagnetic current operator is proportional to a linear combination of the neutral vector meson field operators. Neglecting the phi-omega complex, this should give a good account of the rate of lepton pair emission from a hot pion gas. The mass and width of both transverse and longitudinal rho-mesons increase with temperature, but temperature effects are still relatively small up to T = 150 MeV. If substantial shifts in these quantities were to be seen experimentally, it would seem to require other new physics like chiral symmetry restoration or deconfinement. The results obtained here may be viewed as generalizing the Gounaris-Sakurai formula to finite temperature.