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Solar Physics

, Volume 166, Issue 1, pp 201–208 | Cite as

North-South asymmetry in the solar flare index

  • Tamer Ataç
  • Atila Özgüç
Article

Abstract

This paper reports the results of a study of the N-S asymmetry in the flare index using the results of Knoška (1985) combined with our results for the solar cycles 17 to the current cycle 22. By comparing the time-variation of the asymmetry curve with the solar activity variation of the 11-year cycle, we have found that the flare index asymmetry curve is not in phase with the solar cycle and that the asymmetry peaks during solar minimum. A periodic behaviour in the N-S asymmetry appears: the activity in one hemisphere is more important during the ascending part of the cycle whereas during the descending part the activity becomes more important in the other hemisphere. The dominance of flare activity in the southern hemisphere continues during cycle 22 and, according to our findings, this dominance will increase gradually during the following cycle 23.

Keywords

Flare Solar Activity Southern Hemisphere Solar Cycle Solar Flare 
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 1996

Authors and Affiliations

  • Tamer Ataç
    • 1
  • Atila Özgüç
    • 1
  1. 1.Kandilli Observatory, Bogaziçi UniversityIstanbulTurkey

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