Chemical equilibration of partons in high-energy heavy-ion collisions

Journal Article · Tue Jun 01 00:00:00 EDT 1993 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.47.4905· OSTI ID:6463203

Geiger, K; Kapusta, J I ^[1]

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1. School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

The chemical composition of the hot and dense parton matter formed in the central region of ultrarelativistic heavy-ion collisions is studied for the case of Au+Au collisions at energies reached at the BNL RHIC using the parton cascade model. It is shown that within this framework, which is based on current understanding of semihard and hard interactions in QCD including the emission and absorption of soft partons, a chemical equilibration between the gluons and the quarks cannot be achieved. The gluons and [ital u], [ital d], [ital s], and [ital c] quarks all rapidly approach kinetic equilibrium with a common temperature. The gluons subsequently also achieve chemical equilibrium, but the light quarks only reach about 60% of their ideal chemical equilibrium densities. It is demonstrated that the baryon density in the central region is small relative to the total parton density, with an associated ratio of baryon chemical potential to temperature of 0.35, slowly decreasing with time. The implications of the formation of such a hot, gluon-dominated plasma for strangeness, charm, and dilepton production are discussed.

• DOE Contract Number: FG02-87ER40328
• OSTI ID: 6463203
• Journal Information: Physical Review, D (Particles Fields); (United States), Journal Name: Physical Review, D (Particles Fields); (United States) Vol. 47:11; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

662230* -- Quantum Chromodynamics-- (1992-)
663450 -- Heavy-Ion-Induced Reactions & Scattering-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BOSONS
CHARGED-PARTICLE REACTIONS
CHARMONIUM
CHEMICAL COMPOSITION
COMPOSITE MODELS
ELEMENTARY PARTICLES
ENERGY RANGE
EQUILIBRIUM
FERMIONS
FIELD THEORIES
GLUONS
GOLD 197 REACTIONS
GOLD 197 TARGET
HADRONS
HEAVY ION REACTIONS
INTERACTIONS
MATHEMATICAL MODELS
MESONS
NUCLEAR REACTIONS
PAIR PRODUCTION
PARTICLE MODELS
PARTICLE PRODUCTION
PARTICLE PROPERTIES
PARTON MODEL
PARTONS
POSTULATED PARTICLES
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARKONIUM
QUARKS
RELATIVISTIC RANGE
STRANGENESS
TARGETS