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Volume 61 Supplement 5

Special Issue: Flare-Substorm/Space Weather Topics

Modeling of substorms and flares by the fast reconnection mechanism

Abstract

The 3D spontaneous fast reconnection model is applied to well-known signatures of geomagnetic substorms and solar flares. First, it is applied to the traveling compression regions (TCRs) associated with plasmoids propagating down the tail plasma sheet, known as a definite signature of geomagnetic substorms, and the in-situ satellite observations can be precisely explained, both qualitatively and quantitatively. Then, it is demonstrated that the magnetospheric current wedge drastically evolves through field-aligned currents to link the tail current to the auroral electrojet. It is also found that the well-known morphological features of two-ribbon flares can be explained by the fast reconnection model. In particular, the joule heating, associated with the flare current wedge, is shown to be important for the two-ribbon heating. Therefore, it is suggested that both solar flares and geomagnetic substorms result from the same physical mechanism, i.e., the fast reconnection mechanism.

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Correspondence to M. Ugai.

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Ugai, M., Kondoh, K. & Shimizu, T. Modeling of substorms and flares by the fast reconnection mechanism. Earth Planet Sp 61, 561–564 (2009). https://doi.org/10.1186/BF03352922

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  • DOI: https://doi.org/10.1186/BF03352922

Key words

  • Fast reconnection
  • substorms
  • flares
  • TCR
  • current wedge