Annales Geophysicae (Jul 2017)

Automatic detection of Sfe: a proposal

  • J. J. Curto,
  • S. Marsal,
  • G. Creci,
  • G. Domingo

DOI
https://doi.org/10.5194/angeo-35-799-2017
Journal volume & issue
Vol. 35
pp. 799 – 804

Abstract

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Solar flare effects (Sfe's) are rapid magnetic variations related to the enhancement of the amount of radiation produced during solar flare events. For several minutes, the ionosphere is activated and electron densities, electrical conductivities and electric currents are enhanced. The magnetic signature of a flare is visible in the illuminated hemisphere, and sometimes it shows up as small crochet-like movements in the magnetograms. However, regarding their detection using an automatized procedure, they have been very elusive because their small amplitude, which is close to the level of noise produced by other natural phenomena, and their highly variable irregular shapes make it extremely difficult to apply predesigned patterns. In this paper, we summarize the difficulties that Sfe detection presents and explain a line of work we initiated to overcome these difficulties with the goal of achieving a system capable of performing automatic detection. Some properties of Sfe's, including spherical symmetry around the vortex and different time durations between Sfe's and other natural variations, were used to construct an index allowing us to detect Sfe's.