Single Electron Elliptic Flow Measurements in Au+Au collisions from STAR


Recent measurements of elliptic flow (v_{2}) and the nuclear modification
factor (R_{CP}) of strange mesons and baryons in the intermediate p_{T}
domain in Au+Au collisions demonstrate a scaling = with the
number-of-constituent-quarks [1]. This suggests hadron production via quark
coalescence from a thermalized parton system. Measuring the elliptic flow of
charmed hadrons which are generally believed to originate rather from
fragmentation than from coalescence processes might therefore change our
view of hadron production in heavy ion collisions.

While direct v_{2} measurements of charmed hadrons are currently not
available, single electron v_{2} at sufficiently high transverse = momenta
can serve as a substitute. At transverse momenta above 2 GeV/c , the
production of single electrons from non-photonic sources is expected to be
dominated by the decay of charmed hadrons. Simulations show a strong
correlation between the flow of the charmed hadrons and the flow of their
decay electrons for pT > 2 GeV/c.=20

We will present first results from our single electron v2 measurements from
Au+Au collisions at RHIC energies.

[1] Phys. Rev. Lett. 92 (2004) 052302