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eposcorr (eposcorr-3.13) [xmmsas_20211130_0941-20.0.0]

Output Files

From version 1.1 on the output routine tests if the columns RA_CORR and DEC_CORR are already present in the input/output file. Depending on the presence of these columns it will either add them or modify them. After the task has been run the following items will be present:

  1. X-ray source list with two additional columns, being the corrected RA and DEC called RA_CORR and DEC_CORR.
  2. The following keywords are added to the table: RAOFFSET, DEOFFSET, which indicate the offsets in RA and DEC used to correct the positions; RAOFFERR, DEOFFERR (the associated statistical errors) and LIK_HOOD (containing the likelihood statistic) and NMATCHES. The keywords ROT_CORR (rotational correction) and ROT_ERR (error in rotation) are also added. The keyword LIK_NULL contains the likelihood that can be expected from spurious matches only. It depends on the number of X-ray sources, the distribution of their positional errors, and the surface density of optical sources.
  3. An optional image will be produced containing a map of likelihood values. This image can be used to check the uniqueness of the optimization routine.

XMM-Newton SOC -- 2021-11-30