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arXiv · 0905.4678

Hybrid model calculations of direct photons in high-energy nuclear collisions

Björn Bäuchle·Marcus Bleicher
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Abstract

Direct photon emission in heavy-ion collisions is calculated within a relativistic micro+macro hybrid model and compared to the microscopic transport model UrQMD. In the hybrid approach, the high-density part of the evolution is replaced by an ideal 3-dimensional hydrodynamic calculation. This allows to examine the effects of viscosity and full local thermalization, in comparison of the transport model to the ideal fluid-dynamics. We study the origin of high-p_T photons as well as the impact of elementary high-sqrt(s) collisions. We further explore the contribution of different production channels and non-thermal radiation to the spectrum of direct photons. Detailed comparison to the measurements by the WA98-collaboration are also undertaken.

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Björn Bäuchle, Marcus Bleicher. 2010-03-04. Hybrid model calculations of direct photons in high-energy nuclear collisions. https://doi.org/10.1103/physrevc.81.044904

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