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arXiv · 1307.1576

Instabilities of rotational flows in azimuthal magnetic fields of arbitrary radial dependence

Oleg N. Kirillov·Frank Stefani·Yasuhide Fukumoto
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Abstract

Using the WKB approximation we perform a linear stability analysis for a rotational flow of a viscous and electrically conducting fluid in an external azimuthal magnetic field that has an arbitrary radial profile B_{phi}(R). In the inductionless approximation, we find the growth rate of the three-dimensional perturbation in a closed form and demonstrate in particular that it can be positive when the velocity profile is Keplerian and the magnetic field profile is slightly shallower than R^{-1}.

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Oleg N. Kirillov, Frank Stefani, Yasuhide Fukumoto. 2013-11-15. Instabilities of rotational flows in azimuthal magnetic fields of arbitrary radial dependence. https://doi.org/10.1088/0169-5983%2F46%2F3%2F031403

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