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arXiv · 1201.3093

Measurement of isolated photon production in pp and PbPb collisions at sqrt(sNN) = 2.76 TeV

CMS Collaboration
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Abstract

Isolated photon production is measured in proton-proton and lead-lead collisions at nucleon-nucleon centre-of-mass energies of 2.76 TeV in the pseudorapidity range |eta|<1.44 and transverse energies ET between 20 and 80 GeV with the CMS detector at the LHC. The measured ET spectra are found to be in good agreement with next-to-leading-order perturbative QCD predictions. The ratio of PbPb to pp isolated photon ET-differential yields, scaled by the number of incoherent nucleon-nucleon collisions, is consistent with unity for all PbPb reaction centralities.

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CMS Collaboration. 2013-01-22. Measurement of isolated photon production in pp and PbPb collisions at sqrt(sNN) = 2.76 TeV. https://doi.org/10.1016/j.physletb.2012.02.077

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