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arXiv · 1003.0699

Spectral densities for hot QCD plasmas in a leading log approximation

Juhee Hong·Derek Teaney
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Abstract

We compute the spectral densities of $T^{\mu\nu}$ and $J^{\mu}$ in high temperature QCD plasmas at small frequency and momentum,\, $\omega,k \sim g^4 T$. The leading log Boltzmann equation is reformulated as a Fokker Planck equation with non-trivial 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 quasi-particles to ideal hydrodynamics. This transition is analyzed with conformal and non-conformal second order hydrodynamics, and a second order diffusion equation. We determine all of the second order transport coefficients which characterize the linear response in the hydrodynamic regime.

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Juhee Hong, Derek Teaney. 2010-03-02. Spectral densities for hot QCD plasmas in a leading log approximation. https://doi.org/10.1103/physrevc.82.044908

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