||Direct virtual photon production in Au+Au collisions at √ sNN = 200 GeV
STAR CollaborationEsumi , S.
458 , 2017-07 , Elsevier
We report the direct virtual photon invariant yields in the transverse momentum ranges 1 < pT < 3 GeV/c and 5 < pT < 10 GeV/c at mid-rapidity derived from the dielectron invariant mass continuum region 0.10 < Mee < 0.28 GeV/c2 for 0–80% minimum-bias Au+Au collisions at √sNN = 200 GeV. A clear excess in the invariant yield compared to the nuclear overlap function T AA scaled p + p reference is observed in the pT range 1 < pT <3 GeV/c. For pT >6 GeV/c the production follows T AA scaling. Model calculations with contributions from thermal radiation and initial hard parton scattering are consistent within uncertainties with the direct virtual photon invariant yield.