mdimovie_casexx.mpg: MDI magnetogram movie (3-day interval). casexx notes
                     event xx.

coronalhole_casexx.gif: 

Upper panel: Configuration of magentic field inferred by a Potential 
Field Source Surface model (PFSS) using a Wilcox Solar Observatory (WSO) 
synoptic map of magnetic field as boundary condition. The thick black 
line represents magentic neutral line at source surface (current sheet). 
The source surface is set at 2.5 Rs. The blue cross shows footpoint of 
open field with positive sign of magentic field, while the red minus 
shows open field with negative polarity. The contours in black (green) 
represent strength of the positive (negative) magentic field on the photosphere. 
The same contours are also overplotted on the synoptic map of magentic 
field taken at WSO (middle panel). In this way, it is easy to locate 
large-scale configuration of magentic field to the photospheric features. 
The bottom panel shows the corresponding synoptic map of magentic field taken 
by SOHO/MDI. The active regions can be easily identified in this map.

configuration_casexx.gif:

Upper panel: The coronal open (colored dot areas) and closed (the areas
consisting of blue-red field lines) field regions below 1.25 solar radius.
The thick black line represents magnetic neutral line at the source surface.
Middle panel: The radial extension of the boundaries of open field regions
to the source surface. Bottom panel: open fields at the source surface. The
colored areas correspond the soalr surface areas shown in the upper panel.

Acknowledgments: The PFSS code was created by Xuepu Zhao at Stanford 
University.