Solar Physics

, Volume 84, Issue 1–2, pp 153–167 | Cite as

A dynamo theory of solar flares

  • J. R. Kan
  • S.-I. Akasofu
  • L. C. Lee


It is proposed that the solar flare phenomenon can be understood as a manifestation of the electrodynamic coupling process of the photosphere-chromosphere-corona system as a whole. The system is coupled by electric currents, flowing along (both upward and downward) and across the magnetic field lines, powered by the dynamo process driven by the neutral wind in the photosphere and the lower chromosphere. A self-consistent formulation of the proposed coupling system is given. It is shown in particular that the coupling system can generate and dissipate the power of 1029 erg s#X2212;1 and the total energy of 1032 erg during a typical life time (103 s) of solar flares. The energy consumptions include Joule heat production, acceleration of current-carrying particles along field lines, magnetic energy storage and kinetic energy of plasma convection. The particle acceleration arises from the development of field-aligned potential drops of 10–150 kV due to the loss-cone constriction effect along the upward field-aligned currents, causing optical, X-ray and radio emissions. The total number of precipitating electrons during a flare is shown to be of order 1037–1038.


Flare Field Line Solar Flare Radio Emission Magnetic Field Line 
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Copyright information

© D. Reidel Publishing Co 1983

Authors and Affiliations

  • J. R. Kan
    • 1
  • S.-I. Akasofu
    • 1
  • L. C. Lee
    • 1
  1. 1.Geophysical Institute, University of AlaskaFairbanks, FairbanksU.S.A.

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