A catalog of Dimming Regions from the SDO AIA mission

Tuesday, 16 December 2014
Alisdair R Davey, Smithsonian Astrophysical Observatory, Cambridge, MA, United States and Scott William Mcintosh, High Altitude Observatory, Boulder, CO, United States
Created as part of the SDO Feature Finding Team's (FFT) work, the Dimming
Region Module has been running automatically at SAO on processed Level 1.5
AIA 193 A data. It has also been run retroactively over a large percentage
of the the previous data from the mission. A database of the dimming regions
and their associated properties will shortly be available, linking dimming
region detections, output from the FFT flare detective module and the
ability to access the data used directly via the VSO.
( Does this database
provide anything more than catalog pointing to events that the user may be
interested in downloading and studying? We examine the possible scientific
potential from the current database. We look at the effects of the
assumptions used to create an autonomous dimming regions detection module,
such as reduced cadence and resolution, and smoothing. We do this by
comparing to sample events run at full cadence and resolution. We consider
what effect other choices such as minimum dimming size and dimming depth
have on scientific value of the database. Although the module detects all
dimmings types, including Thermal Dimmings, Rotation and Evolution
Artifacts, it is Eruptive Dimmings which are the events of real interest.
Unfortunately differentiating these dimming types automatically is one of
the many challenges that still exist to creating a fully automated dimming
regions module, one that would be more effective in Space Weather Warning