Active longitudes, nonaxisymmetric dynamos and phase mixing
نویسندگان
چکیده
منابع مشابه
Active longitudes, nonaxisymmetric dynamos and phase mixing
We discuss the problem of solar active longitudes from the viewpoint of dynamo theory. We start from a recent observational analysis of the problem undertaken by Berdyugina & Usoskin (2003, A&A, 405, 1121) and Usoskin et al. (2005, A&A, 441, 347) who demonstrated from a study of sunspot data that solar active longitudes rotate differentially, with a small but significant asynchrony between nort...
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A two-dimensional mean field dynamo model is solved where magnetic helicity conservation is fully included. The model has a negative radial velocity gradient giving rise to equatorward migration of magnetic activity patterns. In addition the model develops longitudinal variability with activity patches travelling in longitude. These patches may be associated with active longitudes.
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Context. Using Greenwich sunspot data for 120 years it was recently observed that activity regions on the Sun’s surface tend to lie along smoothly changing longitude strips 180◦apart from each other. After critique of the original paper, the new arguments were found to substantiate the claim. Aims. In this paper we analyse new arguments in some detail. Methods. To check basic arguments about pe...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2005
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20053454