Journal ArticleDOI
The rapid dissipation of magnetic fields in highly conducting fluids
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The dynamical conditions that exist when long straight parallel twisted flux tubes in a highly conducting fluid are packed together in a broad array are treated in this article, and it is shown that in general there is no hydrostatic equilibrium.Abstract:
The dynamical conditions that exist when long straight parallel twisted flux tubes in a highly conducting fluid are packed together in a broad array are treated. It is shown that in general there is no hydrostatic equilibrium. In place of equilibrium, there is a dynamical nonequilibrium, which leads to neutral point reconnection and progressive coalescence of neighboring tubes (with the same sense of twisting); this in turn forms tubes of large diameter and reduced twist. The magnetic energy in the twisting of each tube declines toward zero, being dissipated into small-scale motions of the fluid and thence into heat. Referring to the sun, it is pointed out that the twisting and mutual wrapping is converted directly into fluid motion and heat by the dynamical nonequilibrium, so that the work done by the convection of the footpoints goes directly into heating the corona above.read more
Citations
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Klaus Galsgaard,Åke Nordlund +1 more
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Heating and activity of the solar corona: 3. Dynamics of a low beta plasma with three‐dimensional null points
Klaus Galsgaard,Åke Nordlund +1 more
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Chromospheric and coronal heating mechanisms
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References
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Journal ArticleDOI
Sweet's mechanism for merging magnetic fields in conducting fluids
TL;DR: In this paper, it was shown that two oppositely directed sunspot fields with scales of 104 km could be merged by Sweet's mechanism, if shoved firmly together, in about two weeks; their normal interdiffusion time would be of the order of 600 years.
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Cosmical magnetic fields
TL;DR: Magnetic Field Generation in Electrically-Conducting Fluids by H. K. Moffatt as mentioned in this paper is a seminal work in the field of magnetic field generation in electrically conducting fluids.
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Dynamics of the quiescent solar corona.
TL;DR: In this paper, an analytical model for the quiescent inhomogeneous solar corona is developed on the basis of the hypothesis that looplike structures are the basic coronal building blocks.
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A unifying theory of high-latitude geophysical phenomena and geomagnetic storms
W. I. Axford,C. O. Hines +1 more
TL;DR: In this article, the occurrence at high latitudes of a large number of geophysical phenomena, including geomagnetic agitation and bay disturbances, aurorae, and various irregular distri...
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Theoretical models of magnetic field line merging
TL;DR: A review of the models of magnetic field line merging is given in this paper, where the authors describe the process whereby plasma flows across a surface which separates regions including topologically different magnetic field lines.