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Title: Color instabilities in the quark–gluon plasma

Abstract

When the quark–gluon plasma (QGP) – a system of deconfined quarks and gluons – is in a nonequilibrium state, it is usually unstable with respect to color collective modes. The instabilities, which are expected to strongly influence dynamics of the QGP produced in relativistic heavy-ion collisions, are extensively discussed under the assumption that the plasma is weakly coupled. Here, we begin by presenting the theoretical approaches to study the QGP, which include: field theory methods based on the Keldysh–Schwinger formalism, classical and quantum kinetic theories, and fluid techniques. The dispersion equations, which give the spectrum of plasma collective excitations, are analyzed in detail. We pay particular attention to a momentum distribution of plasma constituents which is obtained by deforming an isotropic momentum distribution. Mechanisms of chromoelectric and chromomagnetic instabilities are explained in terms of elementary physics. The Nyquist analysis, which allows one to determine the number of solutions of a dispersion equation without explicitly solving it, and stability criteria are also discussed. We then review various numerical approaches – purely classical or quantum – to simulate the temporal evolution of an unstable quark–gluon plasma. The dynamical role of instabilities in the processes of plasma equilibration is analyzed.

Authors:
 [1];  [2];  [3]
  1. Jan Kochanowski Univ., Kielce (Poland). Inst. of Physics; National Centre for Nuclear Research, Warsaw (Poland)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States). Physics Dept.
  3. Goethe Univ., Frankfurt (Germany). Franfurt Inst. for Advanced Studies
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1392244
Alternate Identifier(s):
OSTI ID: 1397939
Report Number(s):
BNL-114267-2017-JA
Journal ID: ISSN 0370-1573
Grant/Contract Number:
SC0012704; SC0013470
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physics Reports
Additional Journal Information:
Journal Volume: 682; Journal Issue: C; Journal ID: ISSN 0370-1573
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS

Citation Formats

Mrówczyński, Stanisław, Schenke, Björn, and Strickland, Michael. Color instabilities in the quark–gluon plasma. United States: N. p., 2017. Web. doi:10.1016/j.physrep.2017.03.003.
Mrówczyński, Stanisław, Schenke, Björn, & Strickland, Michael. Color instabilities in the quark–gluon plasma. United States. doi:10.1016/j.physrep.2017.03.003.
Mrówczyński, Stanisław, Schenke, Björn, and Strickland, Michael. Sun . "Color instabilities in the quark–gluon plasma". United States. doi:10.1016/j.physrep.2017.03.003. https://www.osti.gov/servlets/purl/1392244.
@article{osti_1392244,
title = {Color instabilities in the quark–gluon plasma},
author = {Mrówczyński, Stanisław and Schenke, Björn and Strickland, Michael},
abstractNote = {When the quark–gluon plasma (QGP) – a system of deconfined quarks and gluons – is in a nonequilibrium state, it is usually unstable with respect to color collective modes. The instabilities, which are expected to strongly influence dynamics of the QGP produced in relativistic heavy-ion collisions, are extensively discussed under the assumption that the plasma is weakly coupled. Here, we begin by presenting the theoretical approaches to study the QGP, which include: field theory methods based on the Keldysh–Schwinger formalism, classical and quantum kinetic theories, and fluid techniques. The dispersion equations, which give the spectrum of plasma collective excitations, are analyzed in detail. We pay particular attention to a momentum distribution of plasma constituents which is obtained by deforming an isotropic momentum distribution. Mechanisms of chromoelectric and chromomagnetic instabilities are explained in terms of elementary physics. The Nyquist analysis, which allows one to determine the number of solutions of a dispersion equation without explicitly solving it, and stability criteria are also discussed. We then review various numerical approaches – purely classical or quantum – to simulate the temporal evolution of an unstable quark–gluon plasma. The dynamical role of instabilities in the processes of plasma equilibration is analyzed.},
doi = {10.1016/j.physrep.2017.03.003},
journal = {Physics Reports},
number = C,
volume = 682,
place = {United States},
year = {Sun Apr 09 00:00:00 EDT 2017},
month = {Sun Apr 09 00:00:00 EDT 2017}
}

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Cited by: 5works
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  • Starting from a classical kinetic description of the quark-gluon plasma, we derive in the linear response approximation the color response function near thermodynamic equilibrium. From its poles the dispersion relations for the collective color modes (one longitudinal and one transverse) are obtained. The absence of Landau damping in the quark-gluon plasma is shown, and other damping mechanisms are discussed. A common misunderstanding concerning Landau damping in an electron plasma at low momenta is clarified. Finally we find the color correlation function in an equilibrium QCD plasma, using the fluctuation-dissipation theorem. Its relation to the gluon polarization operator in finite temperaturemore » QCD is discussed. The coefficient for color transport (color conductivity) is determined within a relaxation time model. Possible applications in the computation of plasma observables are pointed out.« less
  • The rate of quark-gluon plasma droplet nucleation in superheated hadronic matter is calculated within the MIT bag model. The requirements of color singletness and (to less extent) fixed momentum suppress the nucleation rate by many orders of magnitude, making thermal nucleation of quark-gluon plasma droplets unlikely in ultrarelativistic heavy-ion collisions if the transition is first order and reasonably described by the bag model. {copyright} {ital 1996 The American Physical Society.}
  • We calculate the relaxation time self-consistently to study the damping of collective color modes and the color conductivity in a QGP by deriving self-consistent equations for the damping rates of gluons and quarks to leading order QCD by thermal field dynamics including a chemical potential for quarks. We show that the damping rates are not sensitive to the chemical potential whereas color conductivity is enhanced considerably. {copyright} {ital 1996 The American Physical Society.}
  • We consider the hadronization of a QCD plasma by diffusion of quark-antiquark pairs through the plasma's surface. We apply the principle of detailed balance to argue that the surface is readily penetrable by color-singlet pairs. The resulting blackbody surface brightness exceeds that of other hadronization mechanisms. We note that the volume increase, needed to accommodate the plasma's high entropy in the dilute hadronic phase, compensates most of the combinatoric and statistical factors needed to select such pairs from the plasma. We conclude that the rate of evaporation of preformed pairs is ample to maintain phase equilibrium with a freely expandingmore » meson gas outside the plasma.« less