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Direct photons at low $p_{T}$ measured in PHENIX

D. Peressounko
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Abstract

Direct photon spectra measured at small $p_T$ in p+p, d+Au and Au+Au collisions at $\sqrt{s_{NN}}=200$ GeV are presented. Several measurement techniques including statistical subtraction, tagging, and internal and external conversion were applied and found to produce consistent results. The p+p and d+Au results are found to be in very good agreement with pQCD predictions over the entire $p_T$ range. No excess of direct photons in Au+Au collisions with respect to binary scaled d+Au data is observed within systematic errors.

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D. Peressounko. 2007-02-12. Direct photons at low $p_{T}$ measured in PHENIX. https://doi.org/10.1088/0954-3899%2F34%2F8%2Fs115

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