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Helical Surface Structures

Published online by Cambridge University Press:  26 May 2016

Axel Brandenburg  and
Eric G. Blackman
Axel Brandenburg
Affiliation:
Nordita, Blegdamsvej 17, DK-2100 Copenhagen ø, Denmark
Eric G. Blackman
Affiliation:
Department of Physics & Astronomy, University of Rochester, Rochester NY 14627

Abstract

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Over the past few years there has been growing interest in helical magnetic field structures seen at the solar surface, in coronal mass ejections, as well as in the solar wind. Although there is a great deal of randomness in the data, on average the extended structures are mostly left-handed on the northern hemisphere and right-handed on the southern. Surface field structures are also classified as dextral (= right bearing) and sinistral (= left bearing) occurring preferentially in the northern and southern hemispheres respectively. Of particular interest here is a quantitative measurement of the associated emergence rates of helical structures, which translate to magnetic helicity fluxes. In this review, we give a brief survey of what has been found so far and what is expected based on models. Particular emphasis is put on the scale dependence of the associated fields and an attempt is made to estimate the helicity flux of the mean field vs. fluctuating field.

Type
Session D. Atmospheric Inhomogeneities
Information
Symposium - International Astronomical Union , Volume 210: Modelling of Stellar Atmospheres , 2003 , pp. 233 - 242
Copyright
Copyright © Astronomical Society of the Pacific 2003 

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