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

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.

6 pages, 4 figures. Contribution to Hot Quarks 2008

References in corpus (30)

• Experimental and Theoretical Challenges in the Search for the Quark Gluon Plasma: The STAR Collaboration's Critical Assessment of the Evidence from RHIC Collisions
• Formation of dense partonic matter in relativistic nucleus-nucleus collisions at RHIC: Experimental evaluation by the PHENIX collaboration
• Quark Gluon Plasma an Color Glass Condensate at RHIC? The perspective from the BRAHMS experiment
• The PHOBOS Perspective on Discoveries at RHIC
• Microscopic Models for Ultrarelativistic Heavy Ion Collisions
• Relativistic Hadron-Hadron Collisions in the Ultra-Relativistic Quantum Molecular Dynamics Model (UrQMD)
• A Multi-Phase Transport Model for Relativistic Heavy Ion Collisions
• Thermalization of gluons in ultrarelativistic heavy ion collisions by including three-body interactions in a parton cascade
• Fully integrated transport approach to heavy ion reactions with an intermediate hydrodynamic stage
• Pion and kaon production in central Pb+Pb collisions at 20A and 30A GeV: Evidence for the onset of deconfinement
• Hadronic Production of Thermal Photons
• The Search for the Quark-Gluon Plasma
• Signatures of Quark-Gluon-Plasma formation in high energy heavy-ion collisions: A critical review
• Observation of Direct Photons in Central 158 A GeV 208Pb+208Pb Collisions
• Photon production through $A_1$ resonance in high energy heavy ion collisions
• Effects of Parton Intrinsic Transverse Momentum on Photon Production in Hard-Scattering Processes
• Dissipation and elliptic flow at RHIC
• Hadronization with a confining equation of state
• Anisotropic flow of charged and identified hadrons in the quark-gluon string model for Au+Au collisions at sqrt(s) = 200 GeV
• Dileptons and Photons from Coarse-Grained Microscopic Dynamics and Hydrodynamics Compared to Experimental Data
• Statistical Mechanics of semi-classical colored Objects
• Three-body collisions in Boltzmann-Uehling-Uhlenbeck theory
• Direct photon production from hadronic sources in high-energy heavy-ion collisions
• REAL-TIME DESCRIPTION OF PARTON-HADRON CONVERSION AND CONFINEMENT DYNAMICS
• Hadronization of a Quark-Gluon Plasma in the Chromodielectric Model
• Pseudorapidity shape of elliptic flow as signature for fast equilibration in relativistic heavy-ion collisions at energies up to sqrt(s) = 200 GeV
• Anisotropic flow in Pb+Pb collisions at LHC from the quark gluon string model with parton rearrangement
• Direct photons in Pb+Pb at CERN-SPS from microscopic transport theory
• Direct photons and thermal dileptons: A theoretical review
• The role of three-body collisions in phi-meson production processes near threshold