J/ApJ/746/27 Magellanic Quasars Survey. II. AGNs behind LMC (Kozlowski+, 2012)
The Magellanic Quasars Survey.
II. Confirmation of 144 new active galactic nuclei behind the southern edge of
the Large Magellanic Cloud.
Kozlowski S., Kochanek C.S., Jacyszyn A.M., Udalski A., Szymanski M.K.,
Poleski R., Kubiak M., Soszynski I., Pietrzynski G., Wyrzykowski L.,
Ulaczyk K., Pietrukowicz P.
<Astrophys. J., 746, 27 (2012)>
=2012ApJ...746...27K 2012ApJ...746...27K
ADC_Keywords: Active gal. nuclei ; Magellanic Clouds ; Photometry, VRI ;
Redshifts ; QSOs ; Surveys
Keywords: galaxies: active - Magellanic Clouds - quasars: general
Abstract:
We quadruple the number of quasars known behind the Large Magellanic
Cloud (LMC) from 56 (42 in the Optical Gravitational Lensing
Experiment (OGLE)-III LMC fields) to 200 by spectroscopically
confirming 169 (144 new) quasars from a sample of 845 observed
candidates in four ∼3 deg2 Anglo-Australian Telescope/AAOmega fields
south of the LMC center. The candidates were selected based on their
Spitzer mid-infrared colors, X-ray emission, and/or optical
variability properties in the database of the OGLE microlensing
survey. The contaminating sources can be divided into 115 young
stellar objects (YSOs), 17 planetary nebulae (PNe), 39 Be and 24 blue
stars, 68 red stars, and 12 objects classed as either YSO/PN or blue
star/YSO. There are also 402 targets with either featureless spectra
or too low signal-to-noise ratios for source classification. Our
quasar sample is 50% (30%) complete at I = 18.6 mag (19.3 mag). The
newly discovered active galactic nuclei (AGNs) provide many additional
reference points for proper motion studies of the LMC, and the sample
includes 10 bright AGNs (I < 18 mag) that are potentially suitable for
absorption line studies. Their primary use, however, is for detailed
studies of quasar variability, as they all have long-term, high
cadence, continuously growing light curves from the microlensing
surveys of the LMC. Completing the existing Magellanic Quasars Survey
fields in the LMC and Small Magellanic Cloud should yield a sample of
∼700 well-monitored AGNs, and expanding it to the larger regions
covered by the OGLE-IV survey should yield a sample of ∼3600 AGNs.
Description:
We selected targets from the OGLE-III based on their mid-IR, X-ray,
and/or photometric variability characteristics. The observations were
designed for AAOmega, a 400-fiber spectrograph mounted on the 3.9m
Anglo-Australian Telescope (AAT).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 158 144 Parameters of 144 new AGNs behind the LMC
table4.dat 152 25 Parameters of 25 previously known AGNs behind the LMC
table5.dat 92 677 Parameters of the remaining 677 targeted sources
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/A+A/549/A29 : Quasars behind the Magellanic system (Cioni+, 2013)
J/ApJ/747/107 : QSO Candidates in the MACHO LMC database (Kim+, 2012)
J/ApJS/194/22 : Magellanic Quasars Survey: QSOs behind SMC (Kozlowski+, 2011)
J/ApJS/184/172 : High- and intermediate-mass YSOs in the LMC (Gruendl+, 2009)
J/ApJ/701/508 : 5000 AGNs behind the Magellanic clouds (Kozlowski+, 2009)
J/AJ/136/18 : LMC SAGE. New candidate YSOs (Whitney+, 2008)
J/ApJS/172/383 : AGN candidates in the COSMOS field (Trump+, 2007)
J/AcA/52/241 : QSO candidates in OGLE-II data (Eyer+, 2002)
J/A+AS/143/391 : ROSAT HRI catalogue of LMC X-ray sources (Sasaki+, 2000)
J/AJ/114/2353 : AGNs and QSOs behind nearby galaxies (Crampton+, 1997)
J/ApJS/194/22 : MQS. I. QSOs behind SMC (Kozlowski+, 2011)
J/ApJ/775/92 : MQS. III. AGN behind LMC and SMC (Kozlowski+, 2013)
http://ogle.astrouw.edu.pl/ : OGLE homepage
Byte-by-byte Description of file: table[34].dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [MQS]
5- 26 A22 --- MQS Source name (JHHMMSS.ss+DDMMSS.s(a))
28 A1 --- f_MQS [*] Probable AGN (poor spectra) (1)
30 I1 h RAh [4,5] Hour of Right Ascension (J2000)
32- 33 I2 min RAm Minute of Right Ascension (J2000)
35- 39 F5.2 s RAs Second of Right Ascension (J2000)
41 A1 --- DE- [-] Sign of declination (J2000)
42- 43 I2 deg DEd [68,72] Degree of Declination (J2000)
45- 46 I2 arcmin DEm Arcminute of Declination (J2000)
48- 51 F4.1 arcsec DEs Arcsecond of Declination (J2000)
53- 57 F5.2 mag Vmag [17.2,22.4]?=99.99 The OGLE V band magnitude
59- 63 F5.2 mag Imag [16.7,21.2] The OGLE I band magnitude
65- 69 F5.3 --- z [0.149,3.35] Spectroscopic redshift
71- 85 A15 --- OGLE OGLE-III identification (lmcFFF.F.NNNNNN)
( in Simbad)
87- 92 A6 --- Class KK09 (Cat. J/ApJ/701/508) class (2)
94-137 A44 --- EmLines List of emission lines
139-141 A3 --- MIR? [Y/ ] Existence of mid-IR emission?
143-145 A3 --- X? [Y/ ] Existence of X-ray emission?
147-149 A3 --- Var? [Y/ ] Variable source?
151-158 A8 --- Note Various notes (3)
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Note (1):
* = We identified 144 new quasars behind the LMC. Their basic parameters
(including the identified lines) are presented in Table 3. We also
confirmed the 25 known quasars that were in our target list (Table 4).
Of these known quasars, we had flagged only four as probable quasars
because their spectra were too noisy for reliable classification. We
missed one known quasar, MQS J051140.7-710032.8, which had an extremely
low S/N in our data, although we verified its existence. These five
sources are flagged with an asterisk.
Note (2): The classification scheme is QSO-[AB][ab] or YSO-[AB][ab] according
to the location in color-magnitude diagrams: A and B for IRAC
colors/magnitudes, a and b with the I color from OGLE-III.
Note (3): Note as follows:
YSO = Source incorrectly classified as YSOs in Whitney et al.
(2008, Cat. J/AJ/136/18), in 2MASS (Cutri et al. 2003, Cat. II/246), or
in Gruendl & Chu (2009, Cat. J/ApJS/184/172)
HMXB = Source incorrectly classified as a high mass X-ray binary in
Sasaki et al. (2000, Cat. J/A+AS/143/391).
G = quasar discovered by Geha et al. (2003AJ....125....1G 2003AJ....125....1G),
O = QSO outburst from Clocchiatti et al. (2003IAUC.8258....1C 2003IAUC.8258....1C),
D = quasar discovered by Dobrzycki et al. (2002ApJ...569L..15D 2002ApJ...569L..15D) or
Dobrzycki et al. (2005A&A...442..495D 2005A&A...442..495D),
S1 = Seyfert Type 1 from Schmidtke et al. (1994PASP..106..843S 1994PASP..106..843S),
S2 = Seyfert galaxy from Crampton et al. (1997, Cat. J/AJ/114/2353),
E = emission line galaxy.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- --- [MQS]
5- 23 A19 --- MQS Source name (JHHMMSS.ss+DDMMSS.s)
25 I1 h RAh [4/5] Hour of Right Ascension (J2000)
27- 28 I2 min RAm Minute of Right Ascension (J2000)
30- 34 F5.2 s RAs Second of Right Ascension (J2000)
36 A1 --- DE- [-] Sign of the Declination (J2000)
37- 38 I2 deg DEd [68/72] Degree of Declination (J2000)
40- 41 I2 arcmin DEm Arcminute of Declination (J2000)
43- 46 F4.1 arcsec DEs Arcsecond of Declination (J2000)
48- 53 F6.3 mag Vmag [15.318/22.46]?=99.999 The V band magnitude
55- 60 F6.3 mag Imag [14.923/21.574] The I band magnitude
62- 76 A15 --- OGLE OGLE-III identification (lmcFFF.F.NNNNNN)
( in Simbad)
78- 85 A8 --- Class Our spectral classification (1)
87- 92 A6 --- Scl Simbad match code (object type) (1)
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Note (1): We classified the remaining spectra into YSOs, PNe, Be stars,
blue stars, and red objects, while other/featureless spectra are
marked with an "N". We also matched these objects to SIMBAD and we
give its classification, with "0" meaning no match.
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History:
From electronic version of the journal
References:
Kozlowski et al. Paper I. 2011ApJS..194...22K 2011ApJS..194...22K, Cat. J/ApJS/194/22
Kozlowski et al. Paper III. 2013ApJ...775...92K 2013ApJ...775...92K, Cat. J/ApJ/775/92
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 05-Aug-2013