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Tales of Cataloguing IV -- far-flungers
IV. ** far-flungers -- misc moves over 10 arcmin **
So you look up a brightish quasar on DSS or SDSS-DR8 finding charts but are greeted by empty sky. What now? In my case, in constructing the Million Quasars catalog, I needed to find each optical object. Available clues are object brightness (if provided), expected color, and local radio/X-ray maps & photometric NBCKDE/XDQSO quasar candidates. NBCKDE also provides photometric redshift so can point to a compelling candidate if the magnitude is also right. In this way I've identified hundreds of nearby optical objects which are the obviously correct quasar. Usually these objects are within an arcminute and there is no issue. But they can be farther, and indeed some of them are far-flungers of 10 arcminutes, or 20, or a degree, or 4 degrees, or even, my friends, thrown into the other hemisphere when one hemisphere is not enough. So without further ado I present such objects. Section A: 7 Far-Flungers -- true objects 10 arcminutes from catalogued position. 1) Q 0229+0656 (J023204.5+070954) is moved 972 arcsec to J023204.8+072606, and renamed to 0229+0712. No magnitude is given for this blank-sky object (z=0.903, NED:[VCV96] 022925.7+065641). The discovery paper 1993-ARep-37-466 names it as 0229+0712 while stating a position of B022925.71+065641.3 -- note the misfit of the name with its declination. The Verons' technique was to use the position as master, thus changing the name to 0229+0656. However, the original name B0229+0712 denotes a tile of sky in which I found the true object, v=17.9, radio NVSS J023204.7+072605, X-ray 1RXS J023204.1+072611. I've restored its original name "0229+0712" in the Million Quasars catalog. 2) NGC 2639 C2.4 (J084449.6+542306) is moved 4 degrees south to J084445.2+502253. This Halton Arp quasar (v=19.4 z=2.63, no NED) must be near the galaxy of its name, NGC 2639, but this Veron location is far away. Arp's co-ordinates ("Seeing Red",Apeiron,1998,table 3.2) are exactly 4 degrees to the south, and near the galaxy, indicating a Veron transcription error. 3) XBS J14496-0908 (J144936.6-090829) is moved 18 degrees into the Northern Hemisphere at J144936.6+090830 -- change the "-" to "+". This happened because the original publication "The XMM-Newton Bright Serendipitous Survey", Caccianiga A. et al, 2008-A&A-477-735, mispositioned their object XBSJ144937.5+090826 at 144936.61-090829.6 (note the name is N, the position S). The Verons evidently used the given co-ordinates both for position and truncated name form. The true optical object is v=19.5, z=1.26, no NED. 4) Q 2342+089 (J234433.0+091039) is moved 865 arcsec to J234531.0+090906. This is once again an approximately-located object -- Veron flags these, in case you don't want to work out the B1950 position which here is B2342000+085400, i.e., RA=23.7 hours, decl=8.9 degrees. This object has no magnitude given, z=2.784, NED:[HB89] 2342+080. Inspection reveals an in-your-face quasar, v=18.2, X-ray CXOX J234531.0+090905. 5) Q 1052+04 (J105505.2+041400) is moved 1592 arcseconds to J105510.1+034730. This v=18.1 object (z=3.391, no NED) has an approximate position centered on the sky-tile B105200.0+040000, so the true object can be offset by up to 900 arcsec RA and 1800 arcsec decl. NBCKDE J105510.14+034730.0 (=B105235.0+040331, v=18.5) seems to be the only suitable v=18 candidate, and looks good except that its photometric redshift is only 0.535. However, v=18.1 is quite bright for a z=3.391, and Veron's catalog paper 2010-A&A-518-10 explains (illustrated by its figure 2) that old z=3.3 redshifts (specifically z=3.3) were often wrong because low-z MgII-2800A lines were mistaken for Lyman-alpha. Therefore I have marked J105510.1+034730 as "Q 1052+04" in the Million Quasars catalog. 6) Q 2334+10 (J233702.5+104636) is moved 1065 arcsec to J233731.2+110253. This is an approximately-positioned unpublished Cyril Hazard quasar without a magnitude, z=2.243, NED:[VCV96] Q 2334+10. Hazard quasars are generally flat-spectrum v=18, and two candidate objects are found in this tile of sky, BOSS J233731.23+110253.0 (v=18.4) and SDSS J233730.66+105759.9 (v=18.0). The BOSS project considers the "BOSS" object as a science-primary object (i.e. it will be observed) and the other is not, so on this slender reed I record the BOSS object as "Q 2334+10" in (the next edition of) the Million Quasars catalog. 7) Q 2351+10 (J235403.4+104642) is moved 834 arcsec to J235341.0+105926. This is another approximately-positioned unpublished Hazard quasar, the centre of the tile B233400.0+100000, no magnitude, z=2.379, NED:[VCV96] Q 2351+10. There is only one eligible object which fits the Hazard quasar profile, it is BOSS J235341.05+105926.6, v=18.4. This object has been named Q 2351+10 in the Million Quasars catalog. Section B: 7 true objects 2-9 arcminutes from the catalogued position. 1) Q 0047-2326 (J004957.7-230940 v=. z=3.422, NED:[VCV96] Q 0047-23) is moved 198 arcsec to J005012.0-231000. Another approximately-located unpublished Cyril Hazard quasar. Optical v=18.2. 2) PSS J0052+2405 (J005230.0+240530 v=17.4 z=1.90, no NED) is moved 366 arcsec to J005204.2+240708, and renamed as PSS J0052+2405 (#2) because Veron has two objects of this name. Original position was approximate to 400 arcsec. Optical v=18.4. 3) NGC 157#1 (J003446.3-082347 v=19.0 z=0.756, NED:[VCV96] NGC 157 1) is moved 326 arcsec to J003521.6-082500. Halton Arp quasar, approximately positioned. Optical v=19.8. 4) Q 0112-381 (J011508.4-375106 v=19.0 z=2.28, NED:[HB89] 0112-381) is moved 230 arcsec south to J011508.2-375336. An Ann Savage quasar, with finding chart (plate 13) supplied in 1984-MNRAS-207-393. These finding charts are not easy to read and I'm guessing this one slipped past the Verons. 5) Q 0124-365 (J012704.2-361903 v=19.0 z=1.61, NED:[HB89] 0124-365) is moved 220 arcsec to J012717.6-361835. Also an Ann Savage quasar, same paper and finding charts. The finding chart for 0124-365 was typed as "0124-355" and pen-corrected to "0124-365" but still looks like "355". The finding chart is sparse, with only 3 objects. I think the Verons couldn't find this one -- they did not mark it as optically seen. Took me a while to find it. 6) Q 1532+2332 (J153438.1+232230, v=19.8, z=1.249, no NED) is moved 10 time sec, ie, 137 arcsec, to J153448.0+232232. This is a Halton Arp quasar from Arp H, Burbidge EM, Chu Y, Zhu X, 2001-ApJ-553-L11, table 1, object "Arp 9", which gives the correct co-ordinates. The Verons somehow copied the "48.1" time-seconds as "38.1". 7) Q 2239-386 (J224221.7-382017 v=. z=3.554, NED:[VCV96] Q 2239-386) is moved 232 arcsec to J224237.0-382049. This is an approximately-located unpublished Cyril Hazard object, much the same as ones above. This tile of sky shows no Hazard-pattern flat-spectrum v=18 objects, and the high z=3.554 implies a fainter object. There is one standout object, J224237.0-382049 v=19.8 with X-ray 1RXH J224237.1-382047, and nothing else comes to hand, so this one is selected. Section C: 5 Veron quasars deleted 1-3) "Optical Transients" are here today, then gone forevermore. The current thinking is that they are novae. Three Veron objects were optical transients: Q 0000-029 (v=18 z=2.31, NED:[HB89] 0000-029) and Q 2355+003 (v=19 z=2.84, NED:ZC 2355+003, from 1986-A&A-160-321) and ROTSE J11568+5427 (v=18.1 z=1.02, no NED, from Astronomer's Telegram board) which was mis-positioned by Veron, but it makes no difference as it does not exist. 4-5) Satellite streaks -- two SDSS objects, SDSS J09557+2525 (SDSS J095546.30+252534.8 z=2.262) and SDSS J10162+2649 (SDSS J101615.16+264902.4 z=0.383) were found by DR8 to be satellite streaks and removed. Obvious if you have a look. Section D: 7 Veron quasars moved 1-2 arcminutes. I'll just give the correction for the record. 1) Q 0154-500 (J015607.0-494531 v=18.7 z=2.46) moved about 70 arcsec N to J015606.8-494423 (v=19.2) 2) 2E 0237+3953 (J024100.7+400721 v=18.3 z=0.528) moved 103 arcsec to J024054.7+400606 (v=18.5) 3) TOL 1313-309 (J131628.7-311149 v=18.0 z=0.048) found ~1 arcmin away at J131632.6-311218 (v=17.8) 4) 3C 295.0 (J141120.5+521110 v=19.8 z=0.461) actually 1 arcmin North at J141120.4+521210 (v=19.5) 5) 2E 2141+0400 (J214407.8 v=20.6 z=0.401) moved 1 arcmin to N at J214408.0+085902 (v=19.2) 6) Q 2217+0844 (J222008.7+090002 v=17.6 z=0.228) moved 61 arcsec S to J222008.6+085902 (v=17.9) 7) G 2344-3852 (J234649.2-383520 z=0.041) 80 arcsec W to J234643.8-383521 The Weedman catalogs from 1985-ApJS-57-523 and 1978-ApJ-221-469 (Sramek & Weedman) provide positions typically needing correction by ~30 arcsec to their finding charts. However, Wee 140 was found to be a star by SDSS-DR5, SDSS J160250.34+280541.4. The last posting of this series will showcase ~12 mystery objects that I could not locate. Half of them I moved to an unsure matching object, the other half I deleted as not existing. I will describe each in the hope that someone will have help for them one day. Eric Flesch |
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