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arXiv · 0805.3177

Low mass dilepton production at ultrarelativistic energies

E. L. Bratkovskaya·W. Cassing·O. Linnyk
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Abstract

Dilepton production in $pp$ and $Au+Au$ nucleus-nucleus collisions at $\sqrt{s}$ = 200 GeV as well as in $In+In$ and $Pb+Au$ at 158 A$\cdot$GeV is studied within the microscopic HSD transport approach. A comparison to the data from the PHENIX Collaboration at RHIC shows that standard in-medium effects of the $ρ, ω$ vector mesons - compatible with the NA60 data for $In+In$ at 158 A$\cdot$GeV and the CERES data for $Pb+Au$ at 158 A$\cdot$GeV - do not explain the large enhancement observed in the invariant mass regime from 0.2 to 0.5 GeV in $Au+Au$ collisions at $\sqrt{s}$ = 200 GeV relative to $pp$ collisions.

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E. L. Bratkovskaya, W. Cassing, O. Linnyk. 2008-11-11. Low mass dilepton production at ultrarelativistic energies. https://doi.org/10.1016/j.physletb.2008.11.034

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