Dielectron Production in Heavy Ion Collisions Between 1 and 13AGeV

The measurement of electromagnetic probes in todays heavy ion experiments are an unique tool to investigate the properties of hot, compressed nuclear matter such as in medium modifications of hadrons or the nuclear equations of state (EOS) which would yield a deeper understanding of astrophysical processes like supernovae explosions and the physics of neutron stars. The observation of the modification of the ϱ mass in a dielectron experiment at SIS or AGS energies considerably constrains currently available low density approximations to QCD and would serve as a probe of quark and gluon condensates at finite baryon density[1, 2, 3, 4, 5, 6].