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Reversed-polarity regions


We present results of a statistical study of reversed-polarity regions, RPRs, collected over the past 11 years, 1969–1979.

The 58 RPRs we studied have a lifespan comparable to normal active regions and have no tendency to rotate toward a more normal alignment. They seem to have stable configurations with no apparent evidence suggesting stress due to their anomalous magnetic alignment. Magnetic complexity in RPRs is the key to flare productivity just as it is in normal regions: Our weak field RPRs produce no flares and regions with complex spots produce more flares than regions with non-complex spots by a factor of 5.

The RPRs however, differ from normal regions in the frequency of having complex spots, particularly the long-lived complex spots, in them. Less than 17% of normal ARs have complex spots; less than 1.8% have long-lived complex spots. In contrast, 41% of RPRs have complex spots and 24% have long-lived complex spots.

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Tang, F. Reversed-polarity regions. Sol Phys 75, 179–188 (1982).

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  • Flare
  • Active Region
  • Statistical Study
  • Normal Region
  • Weak Field