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arXiv · 2211.14356

Establishing the Range of Applicability of Hydrodynamics in High-Energy Collisions

Victor E. Ambrus·S. Schlichting·C. Werthmann
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Abstract

We simulate the space-time dynamics of high-energy collisions based on a microscopic kinetic description in the conformal relaxation time approximation, in order to determine the range of applicability of an effective description in relativistic viscous hydrodynamics. We find that hydrodynamics provides a quantitatively accurate description of collective flow when the average inverse Reynolds number is sufficiently small and the early pre-equilibrium stage is properly accounted for. We further discuss the implications of our findings for the (in)applicability of hydrodynamics in proton-proton, proton-nucleus and light nucleus collisions.

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Victor E. Ambrus, S. Schlichting, C. Werthmann. 2022-11-25. Establishing the Range of Applicability of Hydrodynamics in High-Energy Collisions. https://doi.org/10.1103/physrevlett.130.152301

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