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

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.

17 pages, 22 Figures

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Cited by in corpus (15)

• Multi-messenger heavy-ion collision physics
• Dimuon radiation at the CERN SPS within a (3+1)d hydrodynamic+cascade model
• Benchmarking a Non-Equilibrium Approach to Photon Emission in Relativistic Heavy-Ion Collisions
• Prompt, pre-equilibrium, and thermal photons in relativistic nuclear collisions
• Direct photon calculations in heavy-ion collisions at s(NN)**1/2 = 62.4 - 200 AGeV in a (3+1) dimensional hybrid approach
• Photon Signals from Quarkyonic Matter
• Direct Photons in Hydrodynamic Modeling of Relativistic Nuclear Collisions
• A Non-Equilibrium Approach to Photon Emission from the Late Stages of Relativistic Heavy-Ion Collisions
• Transport and hydrodynamic calculations of direct photons at FAIR
• Thermal photon production in Au+Au collisions: viscous corrections in two different hydrodynamic formalisms
• Low mass dimuons within a hybrid approach
• Production of thermal photons in viscous fluid dynamics with temperature-dependent shear viscosity
• Direct Photons from a Hybrid Approach -- Exploring the parameter space
• Soft Photons from transport and hydrodynamics at FAIR energies
• Calculations of direct photon emission in Heavy Ion Collisions at \sqrt{s_NN} = 200 GeV