Marc DeRosa
Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA USA
Seminario de Física Solar y Plasmas Astrofísicos
Instituto de Astronomía y Física del Espacio
CONICET-UBA
The topology of the solar coronal magnetic field has attracted much recent interest, due to its importance in determining (for example) the sector structure of the solar wind, the evolution of coronal hole boundaries, and whether the configurations of coronae overlying active regions are unstable and thus possibly eruption-prone. Software that identifies the topological skeleton (null points, spine lines, separators, and separatrix surfaces) of a spherical vector field in three dimensions has been applied to a long-running time series of potential-field source-surface (PFSS) models of the solar corona. We identify the skeletons for a selection of dates spanning the SOHO, STEREO, and SDO eras, and provide visualizations of these topological features in three dimensions. The selected fields contain several topological features of interest, including exceedingly narrow channels of open field and separators associated with inferred reconnection sites, and evidence of the coronal origins of streamers and pseudostreamers in the heliosphere. Such topological features appear frequently in potential field models of the magnetic corona, thus implying that the actual solar corona is likely to involve even more complex topologies, especially as its dynamics and evolution are taken into account.
Miercoles 12 de octubre 2011, 14hs.
Aula del Edificio IAFE