DOUBLE-DIFFUSIVE INSTABILITIES OF A SHEAR-GENERATED MAGNETIC LAYER

Journal Article · Tue Sep 01 00:00:00 EDT 2009 · Astrophysical Journal (Online)

DOI:https://doi.org/10.1088/0004-637X/702/1/L14; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21333840

Silvers, Lara J; Proctor, Michael R. E. ^[1]; Vasil, Geoffrey M ^[2]; Brummell, Nicholas H ^[3]

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1. Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA (United Kingdom)
2. JILA, University of Colorado, Boulder, CO 80309-0440 (United States)
3. Department of Applied Mathematics and Statistics, University of California, Santa Cruz, CA 95064 (United States)

Previous theoretical work has speculated about the existence of double-diffusive magnetic buoyancy instabilities of a dynamically evolving horizontal magnetic layer generated by the interaction of forced vertically sheared velocity and a background vertical magnetic field. Here, we confirm numerically that if the ratio of the magnetic to thermal diffusivities is sufficiently low then such instabilities can indeed exist, even for high Richardson number shear flows. Magnetic buoyancy may therefore occur via this mechanism for parameters that are likely to be relevant to the solar tachocline, where regular magnetic buoyancy instabilities are unlikely.

• OSTI ID: 21333840
• Journal Information: Astrophysical Journal (Online), Vol. 702, Issue 1; Other Information: DOI: 10.1088/0004-637X/702/1/L14; Country of input: International Atomic Energy Agency (IAEA); ISSN 1538-4357
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
INSTABILITY
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
RICHARDSON NUMBER
SUN