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arXiv · 1807.05212

Fillips in Sandpiles; Spanning Avalanches, Bifurcation and Temporal oscillations

M. N. Najafi·Z. Moghadam
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Abstract

The manipulation of the self-organized critical systems by repeatedly deliberate local relaxations (fillips) affect considerably the dynamics of avalanches and change their evolution. During a fillip, the energy diffuses to the neighboring regions, causing a smoothening of the height filed over the system. The fillips are controlled by a parameter $ζ$ which is related to the number of local smoothening events in an avalanche. The system shows a new (mass and time) scales, leading to some oscillatory behaviors. A bifurcation occurs at some $ζ$ value, above which some oscillations occur in the mean energy, and also in the autocorrelation functions. These oscillations are associated with \textit{spanning avalanches} which are due to the accumulation of energy in the smoothed system. The analysis of the rare event waiting time (REWT) confirms also the appearance of this new time scale. A mean field analysis is presented to explain some results.

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M. N. Najafi, Z. Moghadam. 2018-07-11. Fillips in Sandpiles; Spanning Avalanches, Bifurcation and Temporal oscillations. https://doi.org/10.1103/physreve.99.042120

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