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Collective behavior in a granular jet: Emergence of a liquid with zero surface-tension

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 نشر من قبل Xiang Cheng
 تاريخ النشر 2007
  مجال البحث فيزياء
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We perform the analog to the water bell experiment using non-cohesive granular material. When a jet of granular material, many particles wide, rebounds from a fixed cylindrical target, it deforms into a sharply-defined sheet or cone with a shape that mimics a liquid with zero surface tension. The particulate nature of granular material becomes apparent when the number of particles in the cross-section of the jet is decreased and the emerging sheets and cones broaden and gradually disintegrate into a broad spray. This experiment has its counterpart in the behavior of the quark-gluon plasma generated by collisions of gold ions at the Relativistic Heavy Ion Collider. There a high density of inter-particle collisions gives rise to collective behavior that has also been described as a liquid.


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