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arXiv · 1009.6056

v4 for identified particles at RHIC from viscous hydrodynamics

Matthew Luzum
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Abstract

Using ideal and viscous hydrodynamics, the ratio of azimuthal moments v4/(v2)^2 is calculated for pions, protons, and kaons in sqrt{s}=200 A*GeV Au+Au collisions. For any value of viscosity here is little dependence on particle species. Ideal hydrodynamics and data show a flat curve as a function of pt. Adding viscosity in the standard way destroys this flatness. However, it can be restored by replacing the standard quadratic ansatz for delta f (the viscous correction to the distribution function at freeze-out) with a weaker momentum dependence.

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Matthew Luzum. 2010-09-30. v4 for identified particles at RHIC from viscous hydrodynamics. https://doi.org/10.1088/1742-6596%2F270%2F1%2F012044

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