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The Solar Corona: White Light Polarization and Modelling of the Large Scale Electron Density Distribution

  • P. Cugnon
  • J.-R. Gabryl
Conference paper
Part of the NATO Science Series book series (ASIC, volume 558)

Abstract

The corona is the outer part of the solar atmosphere, visible in white light during the total solar eclipses. As such, it appears constituted of giant loops and of streamers, extending up to several solar radii. The corona is separated from the chromosphere by a narrow transition region with very high temperature gradients. In this very thin layer, the temperature increases from about 10 000 K in the chromosphere up to millions K in the corona. Though considerable progresses have been recently made in this field, the heating of the corona remains a rather unsolved problem of the physics of the corona. This high temperature and the low density imply that the corona is constituted of highly ionized thin plasma. The temperature appears roughly stable between 10 6 and 2 10 6 K (Withbroe [1]). Hydrostatic equilibrium may be assumed for some local investigations, but the existence of the solar wind and of frequent big coronal mass ejections (CME) contradicts this assumption at larger scales.

Keywords

Solar Wind Coronal Mass Ejection Solar Corona Electron Density Distribution Solar Radius 
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

© Springer Science+Business Media Dordrecht 2000

Authors and Affiliations

  • P. Cugnon
    • 1
  • J.-R. Gabryl
    • 1
  1. 1.Royal Observatory of BelgiumBruxellesBelgium

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