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Peculiar Features of the Global Magnetic Field Structure of the Sun in Cycles 21–25
- Authors: Bilenko I.A.1
-
Affiliations:
- Sternberg Astronomical Institute, Moscow State University
- Issue: Vol 65, No 7 (2025)
- Pages: 1112–1124
- Section: Articles
- URL: https://ogarev-online.ru/0016-7940/article/view/376081
- DOI: https://doi.org/10.7868/S3034502225070167
- ID: 376081
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Abstract
Changes in the structure of the global magnetic field (GMF) in cycles 21–24 and at the beginning of cycle 25 are considered. It is shown that the GMF structure differs both in different cycles and at different phases of each cycle. Stable longitudinal structures formed in the epochs of maximum activity display rotation with the Carrington period (CR), which may indicate their connection with local magnetic fields. In each individual structure, two extended longitudinal intervals are distinguished with dominating fields of positive or negative polarity that occupy opposite longitudinal intervals and alternate in the even and odd cycles. An increase in the contribution of the sector structures simultaneously with the increasing chaos in the latter leads to a decrease in the mean magnetic field intensity over a CR in the weak cycles 23–25. It is assumed that the total contribution of changes in the magnetic fields of the polar dipole and the sum of the sector (n=m) and tesseral (n ≠ m ≠ 0) harmonics with even n and odd m are decisive in the formation and cyclic changes in the observed GMF sector structure.
About the authors
I. A. Bilenko
Sternberg Astronomical Institute, Moscow State University
Email: bilenko@sai.msu.ru
Moscow, Russia
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