XMM-Newton Science Analysis System


omdetect (omdetect-5.41) [xmmsas_20230412_1735-21.0.0]

Mosaiced images

Mosaiced image-files are produced by ommosaic and contain three image extendions:

1. A count-rate image
2. An exposure map containing pixel-by-pixel effective exposure times.
3. A quality array containing position-dependent image quality-flags.

All three images are of equal size, pointing and orientation. In preparation for source-detection, mosaiced images undergo an additional and initial process where the count-rates are multiplied uniformly by the median exposure time across the whole image. This artificial step is performed only to enable accurate source detection and is accounted for during aperture-photometry.