Dilepton production in schematic causal viscous hydrodynamics

Journal Article · Tue Feb 15 00:00:00 EST 2011 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.83.024904· OSTI ID:21499430

Song, Taesoo ^[1]; Han, Kyong Chol; Ko, Che Ming ^[2]

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1. Cyclotron Institute, Texas A and M University, College Station, Texas 77843-3366 (United States)
2. Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, Texas 77843-3366 (United States)

Assuming that in the hot dense matter produced in relativistic heavy-ion collisions, the energy density, entropy density, and pressure as well as the azimuthal and space-time rapidity components of the shear tensor are uniform in the direction transversal to the reaction plane, we derive a set of schematic equations from the Isreal-Stewart causal viscous hydrodynamics. These equations are then used to describe the evolution dynamics of relativistic heavy-ion collisions by taking the shear viscosity to entropy density ratio of 1/4{pi} for the initial quark-gluon plasma (QGP) phase and of 10 times this value for the later hadron-gas (HG) phase. Using the production rate evaluated with particle distributions that take into account the viscous effect, we study dilepton production in central heavy-ion collisions. Compared with results from the ideal hydrodynamics, we find that although the dilepton invariant mass spectra from the two approaches are similar, the transverse momentum spectra are significantly enhanced at high transverse momenta by the viscous effect. We also study the transverse momentum dependence of dileptons produced from QGP for a fixed transverse mass, which is essentially absent in the ideal hydrodynamics, and find that this so-called transverse mass scaling is violated in the viscous hydrodynamics, particularly at high transverse momenta.

• OSTI ID: 21499430
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 83, Issue 2; Other Information: DOI: 10.1103/PhysRevC.83.024904; (c) 2011 American Institute of Physics; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
DISTRIBUTION
ENERGY DENSITY
ENTROPY
HADRONS
HEAVY ION REACTIONS
HYDRODYNAMICS
LEPTONS
MASS
MASS SPECTRA
PARTICLE RAPIDITY
QUARK MATTER
RELATIVISTIC RANGE
SCALING
SPACE-TIME
TRANSVERSE MOMENTUM
VISCOSITY
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
FLUID MECHANICS
LINEAR MOMENTUM
MATTER
MECHANICS
NUCLEAR REACTIONS
PARTICLE PROPERTIES
PHYSICAL PROPERTIES
SPECTRA
THERMODYNAMIC PROPERTIES