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arXiv · 0902.1927

Relativistic shock waves in viscous gluon matter

I. Bouras·E. Molnar·H. Niemi·Z. Xu·A. El·O. Fochler·C. Greiner·D. H. Rischke
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Abstract

We solve the relativistic Riemann problem in viscous gluon matter employing a microscopic parton cascade. We demonstrate the transition from ideal to viscous shock waves by varying the shear viscosity to entropy density ratio $η/s$ from zero to infinity. We show that an $η/s$ ratio larger than 0.2 prevents the development of well-defined shock waves on timescales typical for ultrarelativistic heavy-ion collisions. Comparisons with viscous hydrodynamic calculations confirm our findings.

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I. Bouras, E. Molnar, H. Niemi, Z. Xu, A. El, O. Fochler, C. Greiner, D. H. Rischke. 2009-07-22. Relativistic shock waves in viscous gluon matter. https://doi.org/10.1103/physrevlett.103.032301

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