Solar Physics

, Volume 94, Issue 2, pp 219–234 | Cite as

Computation of solar magnetic fields from photospheric observations

  • L. Hannakam
  • G. Allen Gary
  • D. L. Teuber
Article
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Revised:

Abstract

The observational difficulties of obtaining the magnetic field distribution in the chromosphere and corona of the Sun has led to methods of extending photospheric magnetic measurements into the solar atmosphere by mathematical procedures. A new approach to this problem presented here is that a constant alpha force-free field can be uniquely determined from the tangential components of the measured photospheric flux alone. The vector magnetographs now provide measurements of both the solar photospheric tangential and the longitudinal magnetic field. This paper presents derivations for the computation of the solar magnetic field from these type of measurements. The fields considered are assumed to be a constant alpha force-free fields or equivalent, producing vanishing Lorentz forces. Consequently, magnetic field lines and currents are related by a constant and hence show an identical distribution. The magnetic field above simple solar regions are described from the solution of the field equations.

Keywords

Atmosphere Magnetic Field Field Equation Field Line Field Distribution 
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 1984

Authors and Affiliations

  • L. Hannakam
    • 1
  • G. Allen Gary
    • 2
  • D. L. Teuber
    • 2
  1. 1.Technical University BerlinBerlinU.S.A.
  2. 2.Space Science Laboratory, NASA Marshall Space Flight CenterHuntsvilleU.S.A.

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