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omqualitymap (omqualitymap-1.5) [xmmsas_20211130_0941-20.0.0]

Example QUALITY map produced by omqualitymap

Figure 1 shows a 16-bit QUALITY image produced by omqualitymap using the image on the left, the original boolean QUALITY image and information from the sources detected on the image.

Figure 1: Example of a QUALITY image (left) produced by omqualitymap using source information derived from the image on the right
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The main features of the QUALITY image are

  1. The circular light-blue region near the centre of the image, which corresponds to the central-enhancement feature.
  2. A vertical brown strip associated with a read-out streak caused by a bright star centred at x=158 and y=192.
  3. A small circular dark-blue region centred on this bright star.
  4. A small circular yellow region, centred at x=143, y=178, associated with a smoke-ring caused by the the previous bright star.
  5. A white strip around the whole image of width 6 pixels.

Figure 2 shows the same QUALITY image after it has been processed by omatt, together with the sky-image. Unfortunately, due to the presence of null pixels in these images, it was not possible to display them in similar colours.

Figure 2: The same images after being processed by omatt
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Figure 3 shows a QUALITY image that has been produced by ommosaic mosaicing the individual QUALITY images in each input sky image.

Figure 3: A mosaiced QUALITY image produced by ommosaic
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The main features of this image are

  1. The borders around each of the input sky images.
  2. The read-out streaks (NB that some do not traverse the whole of the image- to be fixed).
  3. The central enhancement circular region.
  4. Bright sources that produce the read-out streaks.
  5. A circular region round these bright sources to flag fant sources in their vicinity.

XMM-Newton SOC -- 2021-11-30