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Fermi-like behavior of weakly vibrated granular matter

J. E. Fiscina·M. O. Caceres
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Abstract

Vertical movement of zirconia-yttria stabilized 2 mm balls is measured by a laser facility at the surface of a vibrated 3D granular matter under gravity. Realizations z(t) are measured from the top of the container by tuning the fluidized gap with a 1D measurement window in the direction of the gravity. The statistics obeys a Fermi-like configurational approach which is tested by the relation between the dispersions in amplitude and velocity. We introduce a generalized equipartition law to characterize the ensemble of particles which cannot be described in terms of a Brownian motion. The relation between global granular temperature and the external excitation frequency is established.

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J. E. Fiscina, M. O. Caceres. 2005-08-10. Fermi-like behavior of weakly vibrated granular matter. https://doi.org/10.1103/physrevlett.95.108003

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