Automated Coronal Hole Detection using Local Intensity Thresholding Techniques

Details Automated Coronal Hole Detection using Local Intensity Thresholding Techniques Automated Coronal Hole Detection using Local Intensity Thresholding Techniques

2009-05-12

arxiv.org/abs/0905.1814v1

Krista, L. D. and Gallagher, P.T., "Automated Coronal Hole Detection Using Local Intensity Thresholding Techniques", 2009, Sol

Astronomy and Astrophysics

Astrophysics

Solar and Stellar Astrophysics

Scientific paper

10.1007/s11207-009-9357-2

We identify coronal holes using a histogram-based intensity thresholding technique and compare their properties to fast solar wind streams at three different points in the heliosphere. The thresholding technique was tested on EUV and X-ray images obtained using instruments onboard STEREO, SOHO and Hinode. The full-disk images were transformed into Lambert equal-area projection maps and partitioned into a series of overlapping sub-images from which local histograms were extracted. The histograms were used to determine the threshold for the low intensity regions, which were then classified as coronal holes or filaments using magnetograms from the SOHO/MDI. For all three instruments, the local thresholding algorithm was found to successfully determine coronal hole boundaries in a consistent manner. Coronal hole properties extracted using the segmentation algorithm were then compared with in situ measurements of the solar wind at 1 AU from ACE and STEREO. Our results indicate that flux tubes rooted in coronal holes expand super-radially within 1 AU and that larger (smaller) coronal holes result in longer (shorter) duration high-speed solar wind streams.

Affiliated with

Also associated with

No associations

Rating

Automated Coronal Hole Detection using Local Intensity Thresholding Techniques does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Automated Coronal Hole Detection using Local Intensity Thresholding Techniques, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automated Coronal Hole Detection using Local Intensity Thresholding Techniques will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-337021