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Title: Spectral densities for hot QCD plasmas in a leading-log approximation

Abstract

We compute the spectral densities of T{sup {mu}{nu}}and J{sup {mu}}in high-temperature QCD plasmas at small frequency and momentum, {omega},k{approx}g{sup 4}T. The leading log Boltzmann equation is reformulated as a Fokker-Planck equation with nontrivial boundary conditions, and the resulting partial differential equation is solved numerically in momentum space. The spectral densities of the current, shear, sound, and bulk channels exhibit a smooth transition from free-streaming quasiparticles to ideal hydrodynamics. This transition is analyzed with conformal and nonconformal second-order hydrodynamics and a second-order diffusion equation. We determine all of the second-order transport coefficients that characterize the linear response in the hydrodynamic regime.

Authors:
;  [1]
  1. Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794-3800 (United States)
Publication Date:
OSTI Identifier:
21419634
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 82; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevC.82.044908; (c) 2010 The American Physical Society
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; APPROXIMATIONS; BOLTZMANN EQUATION; BOUNDARY CONDITIONS; COMPUTERIZED SIMULATION; FOKKER-PLANCK EQUATION; HYDRODYNAMICS; PLASMA; QUANTUM CHROMODYNAMICS; QUASI PARTICLES; SOUND WAVES; SPECTRAL DENSITY; TRANSPORT THEORY; CALCULATION METHODS; DIFFERENTIAL EQUATIONS; EQUATIONS; FIELD THEORIES; FLUID MECHANICS; FUNCTIONS; INTEGRO-DIFFERENTIAL EQUATIONS; KINETIC EQUATIONS; MECHANICS; PARTIAL DIFFERENTIAL EQUATIONS; QUANTUM FIELD THEORY; SIMULATION; SPECTRAL FUNCTIONS

Citation Formats

Hong, Juhee, and Teaney, Derek. Spectral densities for hot QCD plasmas in a leading-log approximation. United States: N. p., 2010. Web. doi:10.1103/PHYSREVC.82.044908.
Hong, Juhee, & Teaney, Derek. Spectral densities for hot QCD plasmas in a leading-log approximation. United States. doi:10.1103/PHYSREVC.82.044908.
Hong, Juhee, and Teaney, Derek. Fri . "Spectral densities for hot QCD plasmas in a leading-log approximation". United States. doi:10.1103/PHYSREVC.82.044908.
@article{osti_21419634,
title = {Spectral densities for hot QCD plasmas in a leading-log approximation},
author = {Hong, Juhee and Teaney, Derek},
abstractNote = {We compute the spectral densities of T{sup {mu}{nu}}and J{sup {mu}}in high-temperature QCD plasmas at small frequency and momentum, {omega},k{approx}g{sup 4}T. The leading log Boltzmann equation is reformulated as a Fokker-Planck equation with nontrivial boundary conditions, and the resulting partial differential equation is solved numerically in momentum space. The spectral densities of the current, shear, sound, and bulk channels exhibit a smooth transition from free-streaming quasiparticles to ideal hydrodynamics. This transition is analyzed with conformal and nonconformal second-order hydrodynamics and a second-order diffusion equation. We determine all of the second-order transport coefficients that characterize the linear response in the hydrodynamic regime.},
doi = {10.1103/PHYSREVC.82.044908},
journal = {Physical Review. C, Nuclear Physics},
number = 4,
volume = 82,
place = {United States},
year = {Fri Oct 15 00:00:00 EDT 2010},
month = {Fri Oct 15 00:00:00 EDT 2010}
}
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