Week 2 Log

Monday, June 16, 2014

I experimented with thresholds in the IDL code to optimize active region detections. Below are a couple of sample images that show what the code detected in the magnetograms and how it paired the positive and negative regions (white indicates a positive field, black indicates a negative field). These images were produced by varying the threshold values in the code. The image on the left is an example of a bad set of detections, while the image on the right shows a much better set of detections for the same date.

Tuesday, June 17, 2014

I looked at magnetograms from dates when the number of sunspots on the Sun was very high. I selected 15 of these dates that had a lot of active regions to use as test subjects for testing the parameters in the code. Below is a very interesting magnetogram taken during a coronal mass ejection in the Sun. I also attended a lecture on the interior of the Sun (Dana Longcope).

Wednesday, June 18, 2014

I experimented with a couple new parameters designed to merge adjacent active regions. I tested different combinations of these new parameters on magnetograms taken from the dates selected on Tuesday.

Thursday, June 19, 2014

Today I worked to narrow down on the optimal parameter values for the code. I wrote an IDL script to cycle through 243 different parameter combinations for 5 different magnetograms. I plan to examine these images to determine which combination of parameter values produces the best active region detections.

There was also a lecture on magnetic fields in the Sun (Sarah Jaeggli).

Friday, June 20, 2014

Today I examined the images that I took Thursday and determined the optimal parameter values. I then ran the active regions for the 15 dates I found Tuesday. The results look promising; we are almost ready to run the code on the entire dataset! Here is a link to a compressed file containing the images I examined: Parameter Search (Compressed File)