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Self-diffusion in granular gases

Nikolai V. Brilliantov·Thorsten Poeschel
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Abstract

The coefficient of self-diffusion for a homogeneously cooling granular gas changes significantly if the impact-velocity dependence of the restitution coefficient $ε$ is taken into account. For the case of a constant $ε$ the particles spread logarithmically slow with time, whereas the velocity dependent coefficient yields a power law time-dependence. The impact of the difference in these time dependences on the properties of a freely cooling granular gas is discussed.

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Nikolai V. Brilliantov, Thorsten Poeschel. 1999-05-26. Self-diffusion in granular gases. https://doi.org/10.1103/physreve.61.1716

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