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Tales of Cataloguing XV -- last fixes in from the cold
When fixing catalogue errors one naturally wants to catch them all,
but when in so doing you start to encounter new errors caused by your own recent fixes, that shows it's time to (1) clean up all your own errors, and (2) stop. This is why this set of fixes of legacy VCV (Veron-Cetty & Veron v13, 2010-A&A-518-10) quasars, placed here for the record, are truly the last of this "Tales of Cataloguing" series. These changes will appear in the next edition of the Million Quasar (Milliquas) catalogue. (1) Abell 293 was originally thought to be a (Parkes) radio galaxy cluster but Gioia et al. 1984-ApJ-283-495, in addition to discovering a background X-ray quasar with z=1.897 and v=19.7, reported that "also present in this field is a strong point radio source PKS 0159+034 whose position is not coincident with any of the X-ray or optical sources discussed here". In spite of this, VCV assigned both the name "PKS 0159+034" and the redshift 1.897 onto the primary Abell galaxy, thus conflating three objects into one. Gioia et al. provided a finding chart of the quasar but didn't name it, however they placed it as the SE component of an Einstein-detected extended X-ray emission named "1E 0159.1+0330", therefore I've added this quasar (not previously catalogued) with name of "1E 0159.1+0330 SE". Furthermore, my Milliquas algorithm shows the radio source PKS 0159+034, aka FIRST J020151.4+034309, to be associated with 98.6% confidence to a r=21.8 g=22.1 stellar source which is furthermore calculated as 96% likely to be a quasar. But it has no redshift so will continue to appear in Milliquas as a candidate only, henceforth annotated with the name PKS 0159+034. (2) While checking over legacy quasars with unsuitable photometry, I came across the quasar "A4/22" from the "Very Faint Quasar Survey", D. Schade, 1991-AJ-102-869 -- the quasar is listed with z=1.045, v=20.00 and b=20.17. But upon inspection on an SDSS finding chart, the near object is seen to be just a small passive galaxy, so how did David Schade come to call that a quasar? I've seen this situation many times before, so I look for nearby objects, and I look North, South, East, West. And sure enough, at 200 arcseconds due South of the designated spot I see SDSS J110205.85+295914.7 with g=20.00, r=19.71 and u=20.25, a perfect photometric fit. Furthermore, it is a quasar candidate in Gordon Richard's NBCKDE-v3 catalogue (2015-ApJS-219-39) with a photometric redshift of 1.000, well-matched to Schade's spectroscopic redshift of 1.045. Somehow this object got moved ~200 arcsec due North in the preparation of the paper -- looking at Table 4 of the paper, it looks like the declination of the object a4/5 was accidently copied over to a4/22. These things happen. I have moved the identification of "A4/22" over to J110205.85+295914.7, and the author has been informed. (3) LMA 15, in the IC 1613 region, was surveyed by Lequeux/Meyssonnier/Azzopardi 1987-A&AS-67-169 who provided a finding chart which however was too coarse to allow precise identification of the designated object. The astrometry was given but only to whole time seconds, so had an uncertainty of ~15 arcseconds. VCV placed it at the given RA of B010239 (a faint star triplet), the true RA is found to be B010239.9, a blue stellar g=20.7, r=21.2 (PAN-STARRS) for a move of 13.7 arcseconds. (4) KP 1229.0+07.8 from Sramek & Weedman, 1978-ApJ-221-468, #19 on their list, z=1.93, v=20.5. The B1950 astrometry, duly reported by VCV, pointed to nothing (~25 arcseconds away from 3 nearest optical candidates). A coarse finding chart was provided from which, many years ago, I selected the wrong object, SDSS J123134.02+073440.2, a galaxy with r=19.25, g=20.61. I have now moved this to the correct object, SDSS J123134.53+073425.8 with r=21.73, g=21.96, a move of 16.3 arcseconds. Besides the flatter spectrum, it is also clearly a better match to the finding chart, although you do need to stare at it for a while. Done with these now, Eric Flesch 29-Jan-2019 |
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