The Effect of the Differential Rotation of Photospheric Magnetic Features on Synoptic Frames of the Photospheric Magnetic Field
Abstract
To model the time-dependent heliosphere we need the instantaneous global distribution of the photospheric magnetic field. As a proxy for the instantaneous global distribution of the photospheric magnetic field at a particular time of interest, the synoptic frame of the photospheric magnetic field is constructed by inserting into the associated monthly Carrington map of the photospheric magnetic field a remapped magnetogram observed as close as possible to the time of interest. In such a synoptic frame, the observation time of magnetic features in pixels outside the inserted magnetogram may differ from the time of the magnetogram by as much as 14 days. During the interval the magnetic features move significantly due to differential rotation, though it may be acceptable to neglect the effects of meridian flow and random walk diffusion. We improve the synoptic frame by accounting for the differential rotation of the magnetic features in the synoptic background frame and consider how changes in the boundary around the inserted magnetogram due to the differential rotation lead to significant effects on the predicted chromospheric and coronal structures.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2004
- Bibcode:
- 2004AGUFMSH21B0419Z
- Keywords:
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- 7509 Corona;
- 7513 Coronal mass ejections;
- 7524 Magnetic fields;
- 7529 Photosphere