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arXiv · 1311.7223

Experimental evidence for non-axisymmetric magnetorotational instability in a rotating liquid metal exposed to an azimuthal magnetic field

Martin Seilmayer·Vladimir Galindo·Gunter Gerbeth·Thomas Gundrum·Frank Stefani·Marcus Gellert·Günther Rüdiger·Manfred Schultz·Rainer Hollerbach
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Abstract

The azimuthal version of the magnetorotational instability (MRI) is a non-axisymmetric instability of a hydrodynamically stable differentially rotating flow under the influence of a purely or predominantly azimuthal magnetic field. It may be of considerable importance for destabilizing accretion disks, and plays a central role in the concept of the MRI dynamo. We report the results of a liquid metal Taylor-Couette experiment that shows the occurrence of an azimuthal MRI in the expected range of Hartmann numbers.

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Martin Seilmayer, Vladimir Galindo, Gunter Gerbeth, Thomas Gundrum, Frank Stefani, Marcus Gellert, Günther Rüdiger, Manfred Schultz, Rainer Hollerbach. 2014-06-25. Experimental evidence for non-axisymmetric magnetorotational instability in a rotating liquid metal exposed to an azimuthal magnetic field. https://doi.org/10.1103/physrevlett.113.024505

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