Astrophysics and Space Science

, Volume 152, Issue 2, pp 287–311 | Cite as

Soliton and strong Langmuir turbulence in solar flare processes

  • M. T. Song
  • S. T. Wu
  • M. Dryer


The occurrence of modulational instability in the current sheet is investigated. Particular attention is drawn to the plasma micro-instability in this current sheet (i.e., the diffusion region) and its relation to the flare process. It is found that the solitons or strong Langmuir turbulence is likely to occur in the diffusion region under solar flare conditions in which the electric resistivity could be greatly enhanced by several orders of magnitude in this diffusion region. The result is a significant heating and stochastic acceleration of particles. Physically, the occurrence of soliton and strong Langmuir turbulence can be identified with a sudden eruption of an electric current leading to a local vacuum in which an electric potential is formed and results in the release of a huge amount of free energy. A numerical example is used to demonstrate the transition of the magnetic field, velocity, and plasma density from the outer MHD region into the diffusive (resistive) region and, then, back out again with the completion of the energy conversion process. This is all made possible by an increase of resistivity by 4–5 orders of magnitude over the classical value.


Free Energy Soliton Flare Electric Potential Plasma Density 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • M. T. Song
    • 1
  • S. T. Wu
    • 1
  • M. Dryer
    • 2
  1. 1.Center for Space Plasma and Aeronomic ResearchThe University of Alabama at HuntsvilleHuntsvilleUSA
  2. 2.Space Environment Lab/ERL/NOAABoulderUSA

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