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DOE OSTI · 1849554

Tracer particle transport dynamics in the diffusive sandpile cellular automaton

Mier, J. A.·Sánchez, R.·Newman, D. E.
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Abstract

The confinement properties of the diffusive running sandpile are characterized by tracking the motion of a population of marked grains of sand. It is found that, as the relative strength of the avalanching to the diffusive transport channel is varied, a point is reached at which the particle global confinement time and the probability density functions of the jump-sizes and waiting-times of the tracked grains experience a sudden change, thus revealing a dynamical transition, that is consistent with previous studies (Newman DE et al., Phys Rev Lett 2002;88(20):204304). Across this transition, the sandpile moves from a regime characterized by self-similarity and memory, where avalanches of all possible sizes dominate transport across the system, to another regime where transport is taken over by near system-size, quasi-periodic avalanches. Values for the fractional transport exponents that quantify effective transport across the sandpile prior to the transition are also obtained.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS97 MATHEMATICS AND COMPUTINGDiffusive SandpileMathematicsPhysicsSelf-Organized Criticalityfractional transporttracer particles

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Mier, J. A., Sánchez, R., Newman, D. E.. 2020-07-16. Tracer particle transport dynamics in the diffusive sandpile cellular automaton. https://doi.org/10.1016/j.chaos.2020.110117

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