Why the Sunspot Cycle Is Double Peaked

  title={Why the Sunspot Cycle Is Double Peaked},
  author={Katya Georgieva},
  journal={International Scholarly Research Notices},
  • K. Georgieva
  • Published 23 March 2011
  • Physics
  • International Scholarly Research Notices
Many sunspot cycles are double peaked. In 1967, Gnevyshev suggested that actually all cycles have two peaks generated by different physical mechanisms, but sometimes the gap between them is too short for the maxima to be distinguished in indices of the total sunspot activity. Here, we show that indeed all cycles have two peaks easily identified in sunspot activity in different latitudinal bands. We study the double peaks in the last 12 sunspot cycles and show that they are manifestation of the… 

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