Solar Physics

, Volume 106, Issue 1, pp 95–106 | Cite as

The innermost corona observed at the 1973 June 30 eclipse

  • Yoichiro Hanaoka
  • Mitsuo Kanno
  • Hiroki Kurokawa
  • Tokio Tsubaki
Article
Received:

Abstract

Slitless flash spectrograms in heights below 8000 km above the solar limb were obtained by the University of Kyoto Expedition at Atar, Mauritania. The integrated intensities of Fexivλ5303, Fexλ6374, Fexiλ7892, and the continuum are measured as a function of height above the solar limb at eleven points (P.A. = 284–300°) around the third contact point. It is found that a significant amount of the emission in Fexλ6374 originates in chromospheric levels well below 8000 km. This implies that the interspicular region of the chromosphere is occupied by coronal material. The average values of the electron temperature and the electron density in the interspicular region are derived from the Fexλ6374 and the Fexiλ7892 intensities on the assumption of spherical symmetry: Te = 0.9–1.1 × 106 K and Ne = 9–10 × 108 cm−3. The intensity variations of the coronal lines and the continuum with position angle are also studied. Strong correlations between Fexivλ5303 and the continuum and between Fexλ6374 and Fexiλ7892 are found. From the Fexλ6374 intensities it is inferred that there is a density fluctuation in the innermost corona by at least a factor of two.

Keywords

Strong Correlation Contact Point Electron Temperature Intensity Variation Position Angle 
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

© D. Reidel Publishing Company 1986

Authors and Affiliations

  • Yoichiro Hanaoka
    • 1
  • Mitsuo Kanno
    • 1
  • Hiroki Kurokawa
    • 1
  • Tokio Tsubaki
    • 2
  1. 1.Kwasan and Hida ObservatoriesUniversity of KyotoGifuJapan
  2. 2.Department of Earth ScienceShiga UniversityOtsuJapan

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