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PHENIX Direct Photons in 200 GeV p+p and Au+Au Collisions

Justin Frantz
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Abstract

We present the first positive direct photon results in Au+Au at sqrt{s_NN} = 200 GeV along with initial p+p results at the same energy. The p+p result is found to be consistent with NLO perturbative QCD predictions within its large uncertainties. In central Au+Au collisions, an excess over expected background as large as 200-300% is observed from p_T = 4-12 GeV/c. This large signal is shown to be consistent with the scaled pQCD photon prediction, together with suppression of meson background sources.

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Justin Frantz. 2004-04-03. PHENIX Direct Photons in 200 GeV p+p and Au+Au Collisions. https://doi.org/10.1088/0954-3899%2F30%2F8%2F047

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