Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Observation of the resonance frequencies of a stable torus of fluid   We report the first quantitative measurements of the resonance frequencies of
a torus of fluid confined in a horizontal Hele-Shaw cell. By using the
unwetting property of a metal liquid, we are able to generate a stable torus of
fluid with an arbitrary aspect ratio. When subjected to vibrations, the torus
displays azimuthal patterns at its outer periphery. These lobes oscillate
radially, and their number n depends on the forcing frequency. We report the
instability ''tongues'' of the patterns up to n = 25. These resonance
frequencies are well explained by adapting to a fluid torus the usual drop
model of Lord Rayleigh. This approach could be applied to the modeling of
large-scale structures arisen transiently in vortex rings in various domains.

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The categories of this paper are: chem-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: comp-gas
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The categories of this paper are: cs
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The categories of this paper are: patt-sol
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The categories of this paper are: eess
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The categories of this paper are: alg-geom