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Tales of Cataloguing IV -- far-flungers



 
 
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Old October 30th 11, 09:24 AM posted to sci.astro.research
Eric Flesch
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Default 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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