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arXiv · 0706.3432

Fluctuation of the Top Location and Avalanches in the Formation Process of a Sandpile

Chiyori Urabe
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Abstract

We investigate the formation processes of a sandpile using numerical simulation. We find a new relation between the fluctuation of the motion of the top and the surface state of a sandpile. The top moves frequently as particles are fed one by one every time interval T. The time series of the top location has the power spectrum which obeys a power law, S(f)~f^α, and its exponent αdepends on T and the system size w. The surface state is characterized by two time scales; the lifetime of an avalanche, T_{a}, and the time required to cause an avalanche, T_{s}. The surface state is fluid-like when T_{a}~T_{s}, and it is solid-like when T_{a}<<T_{s}. Our numerical results show that αis a function of T_{s}/T_{a}.

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Chiyori Urabe. 2007-06-23. Fluctuation of the Top Location and Avalanches in the Formation Process of a Sandpile. https://doi.org/10.1143/jpsj.76.094401

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