Using a Chandra Source-Finding Algorithm to Automatically Identify Solar X-ray Bright Points
Abstract
We describe adapting a method that is used to find point sources in Chandra X-ray telescope data for use in finding solar X-ray bright points. The algorithm allows selected pixels to be excluded from the source-finding, thus excluding saturated pixels (from flares and/or active regions). For Chandra data the noise is determined by photon-counting statistics, whereas solar telescopes typically integrate a flux. Thus, the calculated signal-to-noise ratio is incorrect, but we find that we can scale the number to get reasonable results. We compare our source-finding to previous Yohkoh results and find a similar number of bright points. Finally, we analyze three sets of data from Hinode, representing different parts of the decline to minimum of the solar cycle. Although these preliminary results are based on a small sample, we see no dependence on the solar cycle.
- Publication:
-
Solar Physics
- Pub Date:
- April 2010
- DOI:
- 10.1007/s11207-009-9456-0
- Bibcode:
- 2010SoPh..262..315A
- Keywords:
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- Data analysis;
- Corona;
- X-ray bright points