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Direct Photons in Heavy-Ion Collisions

Klaus Reygers
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Abstract

A brief overview of direct-photon measurements in ultra-relativistic nucleus-nucleus collisions is given. The results for Pb+Pb collisions at sqrt{s_NN} = 17.3 GeV and for Au+Au collisions at sqrt{s_NN} = 200 GeV are compared to estimates of the direct-photon yield from hard scattering. Both results leave room for a significant thermal photon component. A description purely based on hard scattering processes, however, is not ruled out so far.

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Klaus Reygers. 2006-11-06. Direct Photons in Heavy-Ion Collisions. https://doi.org/10.1063/1.2714431

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