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Solar Physics

, Volume 50, Issue 2, pp 457–464 | Cite as

Observations of coronal polarization at the solar eclipse of 7 March, 1970

  • J. Dürst
Article

Abstract

Polarigraphic observations of the 7 March, 1970 eclipse were made at Miahuatlán (Mexico) with a camera of 120 cm focal length. A polarizing filter in front of the objective could be adjusted at 8 different positions, 22.5° apart. Reduction of eight photographs of the white light corona yields polarization at 72 position angles and from r = 1.1 up to 2.1. High polarization which cannot be explained with Thomson scattering was not observed. An analysation of the measuring accuracy shows, that it is not possible to determine exactly the direction of polarization in the outer corona with the classical method of measuring polarization with a small number of photographs. The coronal hole in the south-west quadrant is analysed. The low intensity and polarization can be explained by a hole with an extent in longitude between 1 and 2 times its extent in latitude and with a minimum electron density between 0 and 0.3 of that outside the hole.

Keywords

Focal Length Measuring Accuracy Classical Method Coronal Hole High Polarization 
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 1976

Authors and Affiliations

  • J. Dürst
    • 1
  1. 1.Swiss Federal ObservatoryZürichSwitzerland

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