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Topology is destiny: Reconnection energetics in the corona

Abstract

Magnetic reconnection is clearly at work in the solar corona reorganizing and simplifying the magnetic field. It has also been hypothesized that this reorganization process somehow supplies the energy heating the corona. We propose a quantitative model relating the topological role (simplification) and the energetic role (heating) of magnetic reconnection. This model is used to analyze multi-wavelength observations of an X-ray bright point. In the model, motion of photospheric sources drives reconnection of coronal flux. If reconnection occurs only sporadically then energy is stored in the coronal field, and released by topological reconnection. We simulate the dynamical response of the plasma to such an energy release, and translate this into predicted observational signatures. The resulting predictions are difficult to reconcile with the observations. This suggests that while reconnection is important in the corona, energy dissipation is governed by other factors, not all of which relate to the topology of the field.

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Correspondence to D. W. Longcope.

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Longcope, D.W., Kankelborg, C.C. Topology is destiny: Reconnection energetics in the corona. Earth Planet Sp 53, 571–576 (2001). https://doi.org/10.1186/BF03353272

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Keywords

  • Current Sheet
  • Magnetic Reconnection
  • Minimum Energy State
  • Fast Reconnection
  • Photospheric Source