Appendix 7. Combined Calibration Scan Images

3. Extracted Source Tables

c. Artifact Identification

The tables have a last column, cc_flg, which is a flag indicating whether or not the source is likely an artifact. The flagged artifacts include filter glints (cc_flg="G"), which were identified using the filter glint mappings from the All-Sky PSC (see II.4b and IV.7) generated from "seed" stars in the combined cal scan extracted sources which have [jhk]_m < 13 in a low-density scan, [jhk]_m < 9 in a high-density scan, and [jhk]_m < 11 in a medium-density scan. The remaining artifacts were identified by eye, using the list of single-band detections as a guide. These artifacts include the random persistence artifact that somehow escaped the filtering naturally resulting from extracting from the north- and south-going cal scan separately; these are listed as cc_flg="P". Also included are those sources which are either part of a bright star diffraction spike or occurred along a spike, to the effect that their photometric and astrometric accuracies are likely compromised by the presence of the spike; these are cc_flg="D". Finally, those sources which do not clearly fall into one of the above categories, but, at least, visually appear to be artifacts; these are cc_flg="A". A clear example are erroneous sources detected across the saturated profile of an extremely bright star in a scan.

[Last Updated: 2004 Sep 26; by S. Van Dyk]

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