  Electromagnetic probes are ideally suited to investigate hot and dense matter
produced in high energy heavy ion collisions. They do not undergo strong
interactions and thus probe the time evolution of the collision. The dielectron
continuum is rich in physics. Dalitz decays of light hadrons and direct decays
of vector mesons, which might be modified in the medium, and correlated charm
decays contribute to the spectrum. Furthermore, exotic states, e.g
quasi-particles predicted to exist in the medium only beyond the phase
transition, might leave their footprint in the continuum. Although correlated
e+e- pairs are rare, the 0.24 nb^-1 collected by PHENIX for Au+Au collisions at
sqrt(s_NN)= 200 GeV in 2004 provides a significant sample to investigate the
dilepton continuum. The continuum and its resonances are separated from the
combinatorial background via an event mixing technique. Mass spectra are
presented and compared with the expectations from decays of hadronic sources.

Nuclear Experiment