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The depletion force in a bi-disperse granular layer

P. Melby·A. Prevost·D. A. Egolf·J. S. Urbach
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Abstract

We demonstrate the effect of the depletion force in experiments and simulations of vertically vibrated mixtures of large and small steel spheres. The system exhibits size segregation and a large increase in the pair correlation function of the large spheres for short distances that can be accurately described using a combination of the depletion potential derived for equilibrium colloidal systems and a Boltzmann factor. The Boltzmann factor defines an effective temperature for the system, which we compare to other measures of the temperature.

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P. Melby, A. Prevost, D. A. Egolf, J. S. Urbach. 2005-07-26. The depletion force in a bi-disperse granular layer. https://arxiv.org/abs/cond-mat/0507623

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