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Granular segregation as a critical phenomenon

Pedro M. Reis·Tom Mullin
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Abstract

We present the results of an experimental study of patterned segregation in a horizontally shaken shallow layer of a binary mixture of dry particles. An order parameter for the segregated structures is defined and the effect of the variation of the combined filling fraction, $C$, of the mixture on the observed pattern formation is systematically studied. The surprising result is that there is a critical event associated with the onset of the pattern, at $C=0.647\pm0.049$, which has the characteristics of a second order phase transition, including critical slowing down.

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Pedro M. Reis, Tom Mullin. 2002-07-16. Granular segregation as a critical phenomenon. https://doi.org/10.1103/physrevlett.89.244301

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