Energy dependence of acceptance-corrected dielectron excess mass spectrum at mid-rapidity in Au+AuAu+Au collisions at sNN=19.6 and 200 GeV

The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1|yee|<1 in minimum-bias Au+AuAu+Au collisions at sNN=19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ   spectral function for Mee<1.1 GeV/c2Mee<1.1 GeV/c2. The integrated dielectron excess yield at sNN=19.6 GeV for 0.4