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Title: Hadronic modes and quark properties in the quark-gluon plasma

Abstract

Based on interaction potentials between a heavy quark and antiquark as extracted from recent QCD lattice calculations, we set up a Brueckner-type many-body scheme to study the properties of light (anti-) quarks in a quark-gluon plasma at moderate temperatures, T{approx_equal} 1-2 T{sub c}. The quark-antiquark T matrix, including both color-singlet and color-octet channels, and corresponding quark self-energies and spectral functions are calculated self-consistently. The repulsive octet potential induces quasiparticle masses of up to 150 MeV, whereas the attractive color-singlet part generates resonance structures in the q-q T matrix, which in turn lead to quasiparticle widths of {approx_equal} 200 MeV. This corresponds to scattering rates of {approx_equal} 1 fm{sup -1} and may reflect liquid-like properties of the system.

Authors:
;  [1]
  1. Cyclotron Institute and Physics Department, Texas A and M University, College Station, Texas 77843-3366 (United States)
Publication Date:
OSTI Identifier:
20771134
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 72; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevC.72.064905; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; B QUARKS; C QUARKS; COLOR MODEL; HEAVY ION REACTIONS; LATTICE FIELD THEORY; MANY-BODY PROBLEM; MEV RANGE; PARTICLE WIDTHS; QUANTUM CHROMODYNAMICS; QUARK MATTER; RESONANCE PARTICLES; S MATRIX; SCATTERING; SELF-ENERGY; SPECTRAL FUNCTIONS; T QUARKS

Citation Formats

Mannarelli, M., and Rapp, R. Hadronic modes and quark properties in the quark-gluon plasma. United States: N. p., 2005. Web. doi:10.1103/PhysRevC.72.064905.
Mannarelli, M., & Rapp, R. Hadronic modes and quark properties in the quark-gluon plasma. United States. doi:10.1103/PhysRevC.72.064905.
Mannarelli, M., and Rapp, R. Thu . "Hadronic modes and quark properties in the quark-gluon plasma". United States. doi:10.1103/PhysRevC.72.064905.
@article{osti_20771134,
title = {Hadronic modes and quark properties in the quark-gluon plasma},
author = {Mannarelli, M. and Rapp, R.},
abstractNote = {Based on interaction potentials between a heavy quark and antiquark as extracted from recent QCD lattice calculations, we set up a Brueckner-type many-body scheme to study the properties of light (anti-) quarks in a quark-gluon plasma at moderate temperatures, T{approx_equal} 1-2 T{sub c}. The quark-antiquark T matrix, including both color-singlet and color-octet channels, and corresponding quark self-energies and spectral functions are calculated self-consistently. The repulsive octet potential induces quasiparticle masses of up to 150 MeV, whereas the attractive color-singlet part generates resonance structures in the q-q T matrix, which in turn lead to quasiparticle widths of {approx_equal} 200 MeV. This corresponds to scattering rates of {approx_equal} 1 fm{sup -1} and may reflect liquid-like properties of the system.},
doi = {10.1103/PhysRevC.72.064905},
journal = {Physical Review. C, Nuclear Physics},
number = 6,
volume = 72,
place = {United States},
year = {Thu Dec 15 00:00:00 EST 2005},
month = {Thu Dec 15 00:00:00 EST 2005}
}
  • We study the properties of quark-antiquark interactions in the Quark-Gluon Plasma at moderate temperatures, T {approx_equal} 1-2 Tc, within a Brueckner-type many-body approach. The quark-antiquark T-matrix, including both color-singlet and -octet channels, and corresponding quark self-energies are evaluated self-consistently. We find that light mesonic states persist as resonances in the Quark-Gluon Plasma up to temperatures T {approx_equal} 1.75Tc and fermionic quasiparticles acquire masses of up to {approx}150 MeV and widths of around {approx}200 MeV.
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  • We introduce a combined macroscopic-microscopic transport approach employing relativistic hydrodynamics for the early, dense, deconfined stage of the reaction and a microscopic nonequilibrium model for the later hadronic stage where the equilibrium assumptions are not valid anymore. Within this approach we study the dynamics of hot, bulk QCD matter, which is expected to be created in ultrarelativistic heavy-ion collisions at the Super Proton Synchrotron, the Relativistic Heavy Ion Collider, and the Large Hadron Collider. Our approach is capable of self-consistently calculating the freeze-out of the hadronic system, while accounting for the collective flow on the hadronization hypersurface generated by themore » QGP expansion. In particular, we perform a detailed analysis of the reaction dynamics, hadronic freeze-out, and transverse flow. (c) 2000 The American Physical Society.« less