  The dilepton radial flow in Au+Au collisions at \sqrt{s_{NN}}=200 GeV is
investigated. The space-time evolution of the fireball is described by a 2+1
dimensional ideal hydrodynamics with a variety of equations of state. The slope
parameters of the transverse momentum spectra from the partonic and hadronic
phases show distinct features and are sensitive to equation of state
parameters. The elliptic flow and breaking of M_T scaling are also studied and
have distinct features for the two phases. These features can serve as clean
signals for the formation of a quark-gluon plasma in ultra-relativistic heavy
ion collisions.
