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Experimental evidence for magnetorotational instability in a helical magnetic field

Frank Stefani·Thomas Gundrum·Gunter Gerbeth·Günther Rüdiger·Manfred Schultz·Jacek Szklarski·Rainer Hollerbach
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Abstract

A recent paper [R. Hollerbach and G. Rudiger, Phys. Rev. Lett. 95, 124501 (2005)] has shown that the threshold for the onset of the magnetorotational instability (MRI) in a Taylor-Couette flow is dramatically reduced if both axial and azimuthal magnetic fields are imposed. In agreement with this prediction, we present results of a Taylor-Couette experiment with the liquid metal alloy GaInSn, showing evidence for the existence of the MRI at Reynolds numbers of order 1000 and Hartmann numbers of order 10.

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Frank Stefani, Thomas Gundrum, Gunter Gerbeth, Günther Rüdiger, Manfred Schultz, Jacek Szklarski, Rainer Hollerbach. 2006-06-20. Experimental evidence for magnetorotational instability in a helical magnetic field. https://doi.org/10.1103/physrevlett.97.184502

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