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XMM-Newton Science Analysis System

ommag (ommag-3.12) [xmmsas_20230412_1735-21.0.0]


This task converts the 'list' of given counts to instrumental magnitudes in the appropriate instrumental bandpasses. The 'list' must be a source-list from OMDETECT. The output file will be a FITS file identical to the input source-list or time-series except that the count-rates have been converted into instrumental magnitudes (in the specified filter bandpass - $U$, $B$, $V$, $UVW1$, $UVM2$, $UVW2$, clear) and the new magnitudes written as an extra column in the source-list FITS file. The program also calculates the limiting magnitude and writes the value in the source-list file. Presently the computed magnitude error is the maximum of the two asymmetric ones.

Please note that no magnitude is computed for corrected count-rates greater than 1000- for such bright sources the count rate is wrong because it is out of coincidence-loss correction. In these cases the magnitude will be set to Null and the significance to the negative of its significance.

XMM-Newton SOC -- 2023-04-16