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28. The magnetic fields of sunspots and the evershed effect

Published online by Cambridge University Press:  18 July 2016

E. Jensen
E. Jensen*
Affiliation:
Institute of Theoretical Astrophysics, Blindern, Oslo, Norway

Abstract

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The observational data on the magnetic fields and the physical parameters in sunspots indicate in a qualitative way how the magnetic lines of force run relative to the isobaric surfaces. If matter is confined to move only along the lines of force it is shown that for sufficient tilt between these lines and the isobars, matter will be accelerated outward along the lines of force. The flow corresponding to this forced convection works as a cooling cap for the core of the spot. It is indicated how a stationary state may be reached with the outward velocity adapted to the temperature difference between the spot and the photosphere.

Type
Part IV: Solar and Interplanetary Magnetic Fields
Information
Symposium - International Astronomical Union , Volume 6: Electromagnetic Phenomena in Cosmical Physics , 1958 , pp. 258 - 262
Copyright
Copyright © Cambridge University Press 1958 

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