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Solar Physics

, Volume 189, Issue 1, pp 25–43 | Cite as

Studies of Solar Helicity Using Vector Magnetograms

  • M.J. Hagyard
  • A.A. Pevtsov
Article

Abstract

Observations of photospheric magnetic fields made with vector magnetographs have been used recently to study helicity on the Sun. In this paper we indicate what can and cannot be derived from vector magnetograms, and point out some potential problems in these data that could affect the calculations of `helicity'. Among these problems are magnetic saturation, Faraday rotation, low spectral resolution, and the method of resolving the ambiguity in the azimuth.

Keywords

Magnetic Field Azimuth Magnetic Saturation Potential Problem Spectral Resolution 
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 1999

Authors and Affiliations

  • M.J. Hagyard
    • 1
  • A.A. Pevtsov
    • 2
  1. 1.Space Sciences LaboratoryNASA Marshall Space Flight CenterU.S.A
  2. 2.Department of PhysicsMontana State UniversityBozemanU.S.A

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