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Title: Hadronic resonances above the QCD phase transition

Journal Article · · AIP Conference Proceedings
DOI:https://doi.org/10.1063/1.1961052· OSTI ID:20722845
 [1]
  1. Bogoliubov Laboratory for Theoretical Physics, JINR Dubna, RU-141980 Dubna (Russian Federation)

We describe matter formed in ultrarelativistic heavy ion collisions within a generalized Hagedorn resonance gas model where hadrons have a vanishing width below the Hagedorn temperature TH and a Hagedorn spectrum-like width above TH. Such an approach not only eliminates the divergence of the thermodynamic functions above TH, but it is able to successfully describe the lattice quantum chromodynamics (QCD) data on the energy density. It also allows to explain the absence of heavy resonance contributions in the fit of the experimentally measured particle ratios at SPS and RHIC energies. We present an application of the approach to the description of the NA50 experiment which suggests that the anomalous suppression of J/{psi} production may be explained by the increase of the effective number of degrees of freedom at the Hagedorn temperature. We estimate the shear viscosity of the generalized Hagedorn resonance gas model and find remarkable agreement with the perfect liquid bound {eta}/s {>=} 1/(4{pi})

OSTI ID:
20722845
Journal Information:
AIP Conference Proceedings, Vol. 775, Issue 1; Conference: HLPR 2004: Joint meeting Heidelberg-Liege-Paris-Rostock on hadronic physics, Spa (Belgium), 16-18 Dec 2004; Other Information: DOI: 10.1063/1.1961052; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
Country of Publication:
United States
Language:
English