J/ApJ/701/508 5000 AGNs behind the Magellanic clouds (Kozlowski+, 2009)
Discovery of 5000 active galactic nuclei behind the Magellanic Clouds.
Kozlowski S., Kochanek C.S.
<Astrophys. J., 701, 508-513 (2009)>
=2009ApJ...701..508K 2009ApJ...701..508K
ADC_Keywords: Active gal. nuclei ; Photometry, infrared ; Magellanic Clouds
Keywords: cosmology: observations - galaxies: active - infrared: galaxies -
quasars: general
Abstract:
We show that using mid-IR color selection to find active galactic
nuclei (AGNs) is as effective in dense stellar fields such as the
Magellanic Clouds as it is in extragalactic fields with low stellar
densities using comparisons between the Spitzer Deep Wide Field Survey
data for the NOAO Deep Wide Field Survey Bootes region and the SAGE
Survey of the Large Magellanic Cloud. We use this to build high-purity
catalogs of ∼5000 AGN candidates behind the Magellanic Clouds. Once
confirmed, these quasars will expand the available astrometric
reference sources for the Clouds and the numbers of quasars with
densely sampled, long-term (>decade) monitoring light curves by well
over an order of magnitude and potentially identify sufficiently
bright quasars for absorption line studies of the interstellar medium
of the Clouds.
Description:
We combine results from studies of the extragalactic NOAO Deep Wide
Field Survey (NDWFS; Jannuzi & Dey, 1999ASPC..191..111J 1999ASPC..191..111J) Bootes field
based on the IRAC Shallow Survey (Eisenhardt et al.
2004ApJS..154...48E 2004ApJS..154...48E), the Spitzer Deep Wide Field Survey (SDWFS; Ashby
et al. 2009, Cat J/ApJ/701/428), and the AGN and Galaxy Evolution
Survey (AGES; C. S. Kochanek et al. 2009, in prep) with the Spitzer
SAGE Survey data (Meixner et al. 2006, Cat. J/AJ/132/2268) and
OGLE-III optical survey (Udalski et al. 2008AcA....58...69U 2008AcA....58...69U,
2008AcA....58...89U 2008AcA....58...89U, 2008AcA....58..329U 2008AcA....58..329U) of the LMC to develop a
simple method of selecting AGNs in these dense stellar fields.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 176 4699 AGN candidates behind the Large Magellanic Cloud
table2.dat 176 657 AGN candidates behind the Small Magellanic Cloud
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See also:
J/ApJ/716/530 : Mid-IR variability from the SDWFS (Kozlowski+, 2010)
J/ApJ/701/428 : The Spitzer Deep, Wide-Field Survey (SDWFS) (Ashby+, 2009)
J/AJ/136/18 : LMC SAGE. New candidate YSOs (Whitney+, 2008)
J/ApJ/655/212 : S3MC IRAC and MIPS photometry (Bolatto+, 2007)
J/ApJ/641/140 : Optical counterparts in the NDWFS Bootes field (Brand+, 2006)
J/AJ/132/2268 : SAGE calibration stars (Meixner+, 2006)
J/A+AS/142/41 : SMC X-ray sources ROSAT PSPC catalogue (Haberl+, 2000)
J/A+AS/139/277 : LMC X-ray sources ROSAT PSPC catalogue (Haberl+, 1999)
http://celestial.berkeley.edu/spitzer : S3MC (Spitzer Survey of the SMC) page
http://irsa.ipac.caltech.edu/data/SPITZER/SAGE/ : SAGE data access
http://irsa.ipac.caltech.edu/data/SPITZER/SDWFS/ : SDWFS data access
Byte-by-byte Description of file: table[12].dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- ID Source identification (JHHMMSS.ss+DDMMSS.s)
(see Nomenclature notes)
22- 30 F9.6 deg RAdeg Right Ascension in decimal degrees (J2000)
32- 41 F10.6 deg DEdeg Declination in decimal degrees (J2000)
43- 48 F6.3 mag [3.6] ?=99.999 Spitzer/IRAC 3.6 micron band magnitude
50- 54 F5.3 mag e_[3.6] ?=9.999 The 1σ error in 3.6mag
56- 61 F6.3 mag [4.5] ?=99.999 Spitzer/IRAC 4.5 micron band magnitude
63- 67 F5.3 mag e_[4.5] ?=9.999 The 1σ error in 4.5mag
69- 74 F6.3 mag [5.8] ?=99.999 Spitzer/IRAC 5.8 micron band magnitude
76- 80 F5.3 mag e_[5.8] ?=9.999 The 1σ error in 5.8mag
82- 87 F6.3 mag [8.0] ?=99.999 Spitzer/IRAC 8.0 micron band magnitude
89- 93 F5.3 mag e_[8.0] ?=9.999 The 1σ error in 8.0mag
95-100 F6.3 mag Vmag ?=99.999 V band magnitude
102-106 F5.3 mag e_Vmag ?=9.999 The 1σ error in Vmag
108-113 F6.3 mag Imag ?=99.999 I band magnitude
115-119 F5.3 mag e_Imag ?=9.999 The 1σ error in Imag
121-135 A15 --- OGLE OGLE-III identification (smc/lmcFFF.F.NNNNNN;
in Simbad)
137-142 A6 --- Type Source type, from color-magnitude diagrams (1)
144-148 F5.2 --- z ?=-1 Redshift
150-176 A27 --- r_z Reference of z (2)
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Note (1): The classification scheme is QSO-[AB][0ab] or YSO-[AB][0ab]
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;
0 means that the source had no optical match (outside the OGLE-III
regions or too faint). See section 2 of the paper for details.
Note (2): In table 1, we indicate if the source is a known quasar if it is
flagged as a "YSO" by Whitney et al. (2008, Cat. J/AJ/136/18), and if
it is within the 90% confidence radius of a ROSAT source ("HP99",
Haberl & Pietsch 1999, Cat. J/A+AS/139/277; <[HP99] NNNN> in Simbad).
We estimate that 30% of the ROSAT identifications will be false
positives. For the ROSAT sources we indicate the ROSAT catalog number
using the format HP99_number. In table 2, if it is flagged as a "YSO"
by Bolatto et al. (2007, Cat. J/ApJ/655/212) and if it is within the
90% confidence radius of a ROSAT source (H00, Haberl et al. 2000, Cat.
J/A+AS/142/41; <[HFP2000] NNN> in Simbad). For the ROSAT sources we
indicate the ROSAT catalog number using format H00_number. A "-1"
indicates no existing reference.
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Nomenclature notes:
For table 1, sources are <[KK2009] SAGE JHHMMSS.ss+DDMMSS.s> and for
table 2, sources are <SSTS3MC DD.dddd+DD.dddd> with truncated coordinates.
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 07-Sep-2011