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arXiv · 1408.0756

Viscous hydrodynamics for strongly anisotropic expansion

Ulrich W. Heinz·Dennis Bazow·Michael Strickland
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Abstract

A new formulation of second-order viscous hydrodynamics, based on an expansion around a locally anisotropic momentum distribution, is presented. It generalizes the previously developed formalism of anisotropic hydrodynamics (aHydro) to include a complete set of dissipative currents for which equations of motion are derived by solving the Boltzmann equation in the 14-moment approximation. By solving the vaHydro equations for a transversally homogeneous, longitudinally boost-invariant system ((0+1)-dimensional expansion) and comparing with the exact solution of the Boltzmann equation in relaxation-time approximation we show that vaHydro performs much better than all other known second-order viscous hydrodynamic approximations.

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Ulrich W. Heinz, Dennis Bazow, Michael Strickland. 2014-08-04. Viscous hydrodynamics for strongly anisotropic expansion. https://doi.org/10.1016/j.nuclphysa.2014.08.082

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