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arXiv · 1412.7902

Direct photon and neutral pion production in pp and Pb-Pb collisions measured with the ALICE experiment at LHC

Abstract

Measurements of direct photon and neutral pion production in heavy-ion collisions provide a comprehensive set of observables characterizing properties of the hot QCD medium. Direct photons provide means to test the initial stage of an AA collision and carry information about the temperature and space-time evolution of the hot medium. Neutral pion suppression probes the parton energy loss in the hot medium. Measurements of neutral meson spectra in pp collisions at LHC energies $\sqrt{s}=$0.9, 2.76, 7 TeV serve as a reference for heavy-ion collisions and also provide valuable input data for parameterization of the QCD parton Fragmentation Functions. In this talk, results from the ALICE experiment on direct photon and neutral pion production in pp and Pb-Pb collisions are summarized.

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Dmitri Peressounko. 2014-12-26. Direct photon and neutral pion production in pp and Pb-Pb collisions measured with the ALICE experiment at LHC. https://arxiv.org/abs/1412.7902

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