English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Origin of the hemispheric asymmetry of solar activity

MPS-Authors
/persons/resource/persons104196

Schüssler,  Manfred
Department Sun and Heliosphere, Max Planck Institute for Solar System Research, Max Planck Society;

/persons/resource/persons103859

Cameron,  Robert H.
Department Sun and Heliosphere, Max Planck Institute for Solar System Research, Max Planck Society;

Locator
There are no locators available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Schüssler, M., & Cameron, R. H. (2018). Origin of the hemispheric asymmetry of solar activity. Astronomy and Astrophysics, 618: A89. doi:10.1051/0004-6361/201833532.


Cite as: http://hdl.handle.net/21.11116/0000-0002-6275-C
Abstract
The frequency spectrum of the hemispheric asymmetry of solar activity shows enhanced power for the period ranges around 8.5 years and between 30 and 50 years. This can be understood as the sum and beat periods of the superposition of two dynamo modes: a dipolar mode with a (magnetic) period of about 22 years and a quadrupolar mode with a period between 13 and 15 years. An updated Babcock–Leighton-type dynamo model with weak driving as indicated by stellar observations shows an excited dipole mode and a damped quadrupole mode in the correct range of periods. Random excitation of the quadrupole by stochastic fluctuations of the source term for the poloidal field leads to a time evolution of activity and asymmetry that is consistent with the observational results.