Some evolutionary aspects of solar acrive regions

Title:

Some evolutionary aspects of solar acrive regions

Creator:

M. J.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:03c6366c-a80a-430d-8d0c-c133a9fd8278
uuid:03c6366c-a80a-430d-8d0c-c133a9fd8278

Subject:

heliophysics, large active regions, and sunspot groups

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

The appearance of isolated sunspot groups as well as clustering in large active regions depends upon a complex dynamo process. Evidence of this dynamo process may be deduced from three different outstanding studies. a) The emergence of new fluxes (spots or flares) is preceded by local cyclonic motions, observed at the photospheric level. In regions of weak magnetic fields ; for example polarity inversion lines, gaps between magnetic "hills" or borders of the facula. This velocity structure is a response with a short scale in time and space to local subphotospheric perturbation and thus creates currents and new magnetic flux. b) Magnetic tracers such as long lived H filaments and sunspots, show that the regions of emergence of new flux (family of sunspot groups, eruptive sites or parasitic polaritics) are related to the existence of limited areas rotating rigidly. These "pivot points" which do not follow dlffcrential rotation, could be anchored more deeply than the active centers themselves. c) A large scale circulation, tied to the global rotation, reflects the motions of the underlying fluid (frozen field). Recent results show the existence of azimuthal rolls which transport upward the deep magnetic field. They move slowly toward the poles, and they appear to govern the cyclicity and to modulate the observed solar rotation. These observational results need to be considered to understand the production and the development of active regions.

Language:

Czech

Rights:

http://creativecommons.org/publicdomain/mark/1.0/
policy:public

Coverage:

69-76

Source:

Publications of the Astronomical Institute of the Academy of Sciences of the Czech Republic | 1987 Volume:63-70 | Number:66

Harvested from:

CDK

Metadata only:

false