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arXiv · 1412.1917

Large-scale superfluid vortex rings at nonzero temperatures

Daniel H. Wacks·Andrew W. Baggaley·Carlo F. Barenghi
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Abstract

We numerically model experiments in which large-scale vortex rings - bundles of quantized vortex loops - are created in superfluid helium by a piston-cylinder arrangement. We show that the presence of a normal fluid vortex ring together with the quantized vortices is essential to explain the coherence of these large-scale vortex structures at nonzero temperatures, as observed experimentally. Finally we argue that the interaction of superfluid and normal fluid vortex bundles is relevant to recent investigations of superfluid turbulence.

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Daniel H. Wacks, Andrew W. Baggaley, Carlo F. Barenghi. 2014-12-05. Large-scale superfluid vortex rings at nonzero temperatures. https://doi.org/10.1103/physrevb.90.224514

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