Hostname: page-component-77c89778f8-vsgnj Total loading time: 0 Render date: 2024-07-17T14:00:13.137Z Has data issue: false hasContentIssue false
  • English
  • Français

On the Relation between Moving Magnetic Features and the Decay Rates of Sunspots

Published online by Cambridge University Press:  14 August 2015

Cornelis Zwaan
Cornelis Zwaan*
Affiliation:
Astronomical Institute, Utrecht, The Netherlands

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Bumba (1963) inferred from plots of areas of sunspot groups against time that stable spots may show a phase of slowest decay which is independent of the spot's area. From the Greenwich Photoheliographic Results we analysed the areas of individual spots. Indeed there is a clear lower limit in the decay rates close to Bumba's value dA/dt ≃ −4.0 × 10−6 visible hemisphere/day However, only a small fraction of regular spots and an even smaller fraction of the irregular spots pass through the phase of slowest decay.

Type
Part VI: Evolution of Chromospheric Fine Structures
Information
Symposium - International Astronomical Union , Volume 56: Chromospheric Fine Structure , 1974 , pp. 233 - 234
Copyright
Copyright © Reidel 1974 

References

Bumba, V.: 1963, Bull. Astron. Inst. Czech. 19, 91.Google Scholar
Gokhale, M. H. and Zwaan, C.: 1972, Solar Phys. 26, 52.Google Scholar
Harvey, K. and Harvey, J.: 1973, Solar Phys. 28, 61.Google Scholar
Zwaan, C.: 1968, Ann. Rev. Astron. Astrophys. 6, 135.Google Scholar