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arXiv · 2201.13294

Early time behavior of spatial and momentum anisotropies in kinetic theory across different Knudsen numbers

Nicolas Borghini·Marc Borrell·Hendrik Roch
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Abstract

We investigate the early time development of the anisotropic transverse flow and spatial eccentricities of a fireball with various particle-based transport approaches using a fixed initial condition. In numerical simulations ranging from the quasi-collisionless case to the hydrodynamic regime, we find that the onset of $v_n$ and of related measures of anisotropic flow can be described with a simple power-law ansatz, with an exponent that depends on the amount of rescatterings in the system. In the few-rescatterings regime we perform semi-analytical calculations, based on a systematic expansion in powers of time and the cross section, which can reproduce the numerical findings.

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Nicolas Borghini, Marc Borrell, Hendrik Roch. 2022-01-31. Early time behavior of spatial and momentum anisotropies in kinetic theory across different Knudsen numbers. https://doi.org/10.1140/epjc/s10052-022-10914-9

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