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Magnetic Helicity and Filaments

Published online by Cambridge University Press:  12 April 2016

M.A. Berger
M.A. Berger*
Affiliation:
Mathematics, University College London, London WC1E 6BT, U.K.

Abstract

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Some of the most dramatic images of prominences show helical structure. Helical structure, as well as other structural features such as twist, shear, and linking, can be quantified using helicity integrals. This paper reviews how the calculation of helicity may be applied to prominence models. Recent observations indicate that the sign of helicity in an active region depends on which hemisphere the region is in. The source of this asymmetry is an important problem in solar physics. The total helicity of each hemisphere obeys a Poynting-like theorem which describes how helicity is transferred across the photosphere and the equator. Estimating this helicity transfer may help us in understanding the helicity balance of the sun.

Type
Filaments and Their Environment
Information
International Astronomical Union Colloquium , Volume 167: New Perspectives on Solar Prominences , 1998 , pp. 102 - 110
Copyright
Copyright © Astronomical Society of the Pacific 1998

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