Dielectron azimuthal anisotropy at mid-rapidity in Au + Au collisions at $\sqrt{s_{_{NN}}} = 200$ GeV

We report on the first measurement of the azimuthal anisotropy (v2) of dielectrons (e+e− pairs) at mid-rapidity from sNN=200 GeV Au + Au collisions with the STAR detector at the Relativistic Heavy Ion Collider (RHIC), presented as a function of transverse momentum (pT) for different invariant-mass regions. In the mass region Mee<1.1 GeV/c2 the dielectron v2 measurements are found to be consistent with expectations from π0,η,ω, and ϕ decay contributions. In the mass region 1.1<Mee<2.9GeV/c2, the measured dielectron v2 is consistent, within experimental uncertainties, with that from the cc¯ contributions.

Note:

15 pages, 22 figures, published at PRC

25.75.Cj
25.75.Ld
angular distribution: anisotropy
Brookhaven RHIC Coll
transverse momentum dependence
STAR
heavy ion: scattering
gold
electron positron: mass spectrum
electron positron: elliptic flow

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