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Numerical 3-D Simulations of the Collapse of Photospheric Flux Tubes

Published online by Cambridge University Press:  04 August 2017

Ake Nordlund*
Affiliation:
Copenhagen University Observatory

Extract

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The interaction of photospheric granular convection with a small scale magnetic field has been simulated numerically in a three-dimensional model, with an extension of techniques recently used to simulate field-free granulation. The evolution of an initially homogeneous magnetic field was followed numerically, both in a kinematic (weak-field limit) description, and in a dynamic description, where the back-reaction of the field on the motion through the Lorentz force is taken into account. The simulations illustrate the strong tendency for the field to be swept up and concentrated in the inter-granular lanes because of the topology of the granular flow. The convectively unstable stratification allows field concentration up to a kilogauss field because the temperature reduction in the magnetic plasma.

Type
I. Magnetic Fields in Stellar Photospheres
Copyright
Copyright © Reidel 1983 

References

Carreras, B., Hicks, H.R., Holmes, J.A., Waddell, B.V.: 1980, Phys. Fluids 23, 1811.CrossRefGoogle Scholar
Galloway, D.J., Moore, D.R.: 1979, Geophysic. Astrophys. Fluid Dyn. 12, 73.Google Scholar
Nordlund, Å. 1982, Astron. Astrophys. 107, 1.Google Scholar
Parker, E.N.: 1955, Astrophys. J. 121, 491.Google Scholar
Parker, E.N.: 1978, Astrophys. J. 221, 368.Google Scholar
Parker, E.N.: 1979, “Cosmical Magnetic Fields”, Clarendon Press, Oxford Google Scholar
Spruit, H.: 1976, Solar Phys. 50, 269.CrossRefGoogle Scholar
Spruit, H.: 1977, Solar Phys. 55, 3.Google Scholar
Spruit, H.: 1979, Solar Phys. 61, 363.Google Scholar
Stenflo, J. O.: 1977, in Bonnet, R. M. and Delache, P. (eds.), “The Energy Balance and Hydrodynamics of the Solar Chromosphere and Corona”, IAU Coll. 36, 143.Google Scholar
Waddell, B.V., Carreras, B., Hicks, H.R., Holmes, J.A.: 1979, Phys. Fluids 22, 896.Google Scholar
Webb, A.R., Roberts, B.: 1978, Solar Phys. 59, 249.Google Scholar