Solar Physics

, Volume 113, Issue 1–2, pp 241–248 | Cite as

The resistances of the photosphere and of a flaring coronal loop

  • D. B. Melrose
  • A. N. McClymont


We consider two aspects of solar flares from the point of view of circuit theory. First, we show that the so-called “dynamo models”, which invoke an analogy between the Earth's magnetosphere-ionosphere circuit and the solar corona-photosphere circuit, are illfounded. Second, we consider the rate of coronal energy release in the impulsive phase of a modest flare, and show that, if the energy going into mass motion can be neglected, the corona must present a resistance of about 10−3 μ. Classical resistivity, even in a highly filamented circuit, cannot provide so high a resistance. Anomalous resistivity due to ion sound turbulence can provide the required resistance in this case, but is insufficient to explain the very high power levels inferred in some fast spikes.


Flare High Power Energy Release Power Level Solar Flare 


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Copyright information

© D. Reidel Publishing Company 1987

Authors and Affiliations

  • D. B. Melrose
    • 1
  • A. N. McClymont
    • 1
  1. 1.Institute for Astronomy, University of HawaiiHonoluluUSA

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