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XMM-Newton Science Analysis System


omdetect (omdetect-5.14.2) [???]

Meta Index / Home Page / Algorithm / The detection algorithms

Extended-source Validation Function

omdetect uses several validation functions, and the discussion that follows refers to the one that is used the most frequently.

The function carries out various checks on the list of pixels assigned to the source, which include the following-

1. Check the quantities imax-imin, jmax-jmin, where imin, imax, jmin, jmax, are the minimim/maximum values of the source-pixels x/y coordinates, to ensure that the source is not just a single line of pixels in the x/y direction.
2. Check the pixels in the vicinity of the source pixels to ensure that the pixels are not just part of a much brighter source.
3. Compute the signal-to-noise of the source to ensure it has a value greater than or equal to the minimum allowed value.