Dynamical freeze-out condition in ultrarelativistic heavy ion collisions

Journal Article · Tue Apr 15 04:00:00 EDT 2008 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.77.044907· OSTI ID:21189927

Eskola, K J; Niemi, H; Ruuskanen, P V ^[1]

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1. Department of Physics, P. O. Box 35, FIN-40014 University of Jyvaeskylae (Finland) and Helsinki Institute of Physics, P. O. Box 64, FIN-00014 University of Helsinki (Finland)

We determine the decoupling surfaces for the hydrodynamic description of heavy ion collisions at RHIC and LHC by comparing the local hydrodynamic expansion rate with the microscopic pion-pion scattering rate. The pion p{sub T} spectra for nuclear collisions at BNL Relativistic Heavy Ion Collider (RHIC) and CERN Large Hadron Collider (LHC) are computed by applying the Cooper-Frye procedure on the dynamical-decoupling surfaces and compared with those obtained from the constant-temperature freeze-out surfaces. Comparison with RHIC data shows that the system indeed decouples when the expansion rate becomes comparable with the pion scattering rate. The dynamical decoupling based on the rates comparison also suggests that the effective decoupling temperature in central heavy ion collisions remains practically unchanged from RHIC to LHC.

• OSTI ID: 21189927
• Journal Information: Physical Review. C, Nuclear Physics, Journal Name: Physical Review. C, Nuclear Physics Journal Issue: 4 Vol. 77; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BNL
BROOKHAVEN RHIC
CERN
CERN LHC
COLLISIONS
COMPARATIVE EVALUATIONS
DECOUPLING
EXPANSION
HEAVY ION REACTIONS
PION-PION INTERACTIONS
PIONS
RELATIVISTIC RANGE
SCATTERING
SPECTRA
SURFACES