Energy dependence of acceptance-corrected dielectron excess mass spectrum at mid-rapidity in Au$+$Au collisions at $\sqrt{s_{NN}} =$ 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 in minimum-bias Au+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/c2 . The integrated dielectron excess yield at sNN=19.6 GeV for 0.4

Note:

9 pages, 6 figures

25.75.Cj
25.75.Dw
charged particle: multiplicity
impact parameter: dependence
electron positron: mass spectrum
rho(770): spectral representation
energy dependence
lifetime
nuclear matter: density
nuclear matter: temperature

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