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arXiv · 1408.2371

Direct photon production in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV at STAR

Chi Yang
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Abstract

We present the direct photon production for $1<p_{T}<10$ GeV/$c$ derived from continuum in the dielectron invariant mass region $0.1<M_{ee}<0.3$ GeV/$c^{2}$ from one billion $\sqrt{s_{NN}}=200$ GeV Au+Au events taken in year 2010 and 2011. A clear excess in the invariant yield compared to the number of binary collision scaled $p+p$ reference is observed in the \pt~range 1-4 GeV/$c$. Model calculations with contributions from thermal radiation and initial hard parton scattering are consistent within uncertainties with the direct photon invariant yield.

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Chi Yang. 2014-08-11. Direct photon production in Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV at STAR. https://doi.org/10.1016/j.nuclphysa.2014.08.042

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