Recent results on jet energy loss and direct photons at RHIC

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Abstract.

Measurements of the π0 and direct photon nuclear modification factors in p+p and A+A collisions in the PHENIX experiment at RHIC will be reviewed and recent results at \(\sqrt{S_{NN}}=62.4\) GeV will be presented. Using for the first time the p+p reference measured in the same experiment instead of averaging world data the π0 suppression turns out to be almost as large at \(\sqrt{s_{NN}}=62.4\) GeV as at \(\sqrt{s_{NN}}=200\) GeV, implying gluon densities dNg/dy>800. Possible origins of photon suppression at high pT in \(\sqrt{s_{NN}}=200\) GeV are discussed in light of the new results on photon RAA at \(\sqrt{s_{NN}}=62.4\) GeV.

Keywords

European Physical Journal Special Topic Quark Matter Direct Photon Gluon Density Parton Distribution Function 

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Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2008

Authors and Affiliations

  1. 1.Brookhaven National LaboratoryUptonUSA

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