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High-pT Direct-Photon Results from PHENIX

Klaus Reygers
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Abstract

Direct-photon measurements in p+p and Au+Au collisions at sqrt{s_{NN}} = 200 GeV from the PHENIX experiment are presented. The p+p results are found to be in good agreement with next-to-leading-order (NLO) perturbative QCD calculations. Direct-photon yields in Au+Au collisions scale with the number of inelastic nucleon-nucleon collisions and don't exhibit the strong suppression observed for charged hadrons and neutral pions. This observation is consistent with models which attribute the suppression of high-pT hadrons to energy loss of quarks and gluons in the hot and dense medium produced in Au+Au collisions at RHIC.

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Klaus Reygers. 2005-12-07. High-pT Direct-Photon Results from PHENIX. https://arxiv.org/abs/hep-ex/0512015

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