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arXiv · 0810.0488

Direct photon emission from hadronic sources: Hydrodynamics vs. Transport theory

Bjoern Baeuchle·Marcus Bleicher
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Abstract

Direct photon emission in heavy-ion collisions is calculated within the relativistic microscopic transport model UrQMD. We compare the results from the pure transport calculation to a hybrid-model calculation, where the high-density part of the evolution is replaced by an ideal 3-dimensional fluiddynamic calculation. The effects of viscosity, present in the transport model but neglected in ideal fluid-dynamics, are examined. We study the contribution of different production channels and non-thermal collisions to the spectrum of direct photons. Detailed comparison to the measurements by the WA~98-collaboration are undertaken.

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Bjoern Baeuchle, Marcus Bleicher. 2009-03-08. Direct photon emission from hadronic sources: Hydrodynamics vs. Transport theory. https://doi.org/10.1140/epjc%2Fs10052-009-0987-1

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