J/ApJ/698/1095 The FIRST-2MASS red QSO survey. II. (Urrutia+, 2009)
The FIRST-2MASS red quasar survey.
II. An anomalously high fraction of LoBALs in searches for dust-reddened
quasars.
Urrutia T., Becker R.H., White R.L., Glikman E., Lacy M., Hodge J.,
Gregg M.D.
<Astrophys. J., 698, 1095-1109 (2009)>
=2009ApJ...698.1095U 2009ApJ...698.1095U
ADC_Keywords: Surveys ; Redshifts ; QSOs ; Photometry, SDSS ; Radio sources ;
Photometry ; Infrared sources
Keywords: galaxies: active - galaxies: evolution - quasars: absorption lines -
quasars: general
Abstract:
We present results on a survey to find extremely dust-reddened Type 1
quasars. Combining the FIRST radio survey, the 2MASS Infrared Survey
and the Sloan Digital Sky Survey, we have selected a candidate list of
122 potential red quasars. With more than 80% spectroscopically
identified objects, well over 50% are classified as dust-reddened Type
1 quasars, whose reddenings (E(B-V)) range from approximately 0.1 to
1.5mag. They lie well off the color selection windows usually used to
detect quasars and many fall within the stellar locus, which would
have made it impossible to find these objects with traditional color
selection techniques. The reddenings found are much more consistent
with obscuration happening in the host galaxy rather than stemming
from the dust torus. We find an unusually high fraction of broad
absorption line (BAL) quasars at high redshift, all but one of them
belonging to the low-ionization BAL (LoBAL) class and many also
showing absorption in the metastable FeII line (FeLoBAL). The
discovery of further examples of dust-reddened LoBAL quasars provides
more support for the hypothesis that BAL quasars (at least LoBAL
quasars) represent an early stage in the lifetime of the quasar. The
fact that we see such a high fraction of BALs could indicate that the
quasar is in a young phase in which quasar feedback from the BAL winds
is suppressing star formation in the host galaxy.
Description:
To create a list of candidate red quasars, the 2MASS All-Sky Point
Source Catalog (Cat. II/246) was matched to the FIRST source catalog
(Becker et al., 1995ApJ...450..559B 1995ApJ...450..559B) within 2". We then matched the
FIRST-2MASS catalog to the approximately 215 million sources in the
DR5 SDSS (Cat. VII/252) imaging catalog within 2". We filter the
F2M-SDSS catalog for objects that are very red, i.e., r'-K>5. This
extremely red color filter leaves us with 603 objects inspected bye
eye. The J-K>1.3 color filter further reduces our catalog to 122
sources, which is our final F2MS catalog.
To identify the red quasar candidates, we conducted follow-up
spectroscopy. Our spectroscopic observations were conducted mostly at
the 10m Keck telescope with the ESI instrument.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 154 122 Properties and identification of red quasar
candidates
table2.dat 46 51 Spectral properties of the quasars
table3.dat 71 21 Absorption trough properties of quasars with z>0.9
refs.dat 88 43 References
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See also:
VII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)
VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)
VIII/71 : The FIRST Survey Catalog, Version 03Apr11 (Becker+ 2003)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
VII/240 : Millennium Galaxy Catalogue (Liske+, 2003)
VII/204 : Galaxy properties at NGP (Odewahn+ 1995)
VIII/53 : The Green Bank Survey (Maslowski+ 1972-87)
J/ApJ/667/673 : FIRST-2MASS red quasar survey (Glikman+, 2007)
J/AJ/126/63 : Host galaxies of 2MASS-QSOs with z≤3 (Hutchings+, 2003)
J/AJ/126/2125 : SDSS candidate type II quasars (Zakamska+, 2003)
J/ApJ/569/23 : Optical polarisation of 2MASS QSOs (Smith+, 2002)
J/ApJS/135/227 : The FIRST bright quasar survey. III. (Becker+, 2001)
J/A+AS/128/153 : Revised GB/GB2 sample of radio sources (Machalski 1998)
J/A+AS/109/147 : ROSAT AGN content (Brinkmann+, 1995)
J/ApJS/100/1 : Second Caltech-Jodrell Bank VLBI Survey. II. (Henstock+ 1995)
J/A+AS/96/389 : Warm IRAS sources. II. (de Grijp+, 1992)
J/A+AS/65/267 : A 5-GHz Survey of Radio Sources (Altschuler 1986)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq [1/122] Running sequence number identification
(<[UBW2009] NNN> in Simbad)
5- 6 I2 h RAh FIRST hour of right ascension (J2000)
8- 9 I2 min RAm FIRST minute of right ascension (J2000)
11- 15 F5.2 s RAs FIRST second of right ascension (J2000)
17 A1 --- DE- FIRST sign of the declination (J2000)
19- 20 I2 deg DEd FIRST degree of declination (J2000)
22- 23 I2 arcmin DEm FIRST arcminute of declination (J2000)
25- 29 F5.2 arcsec DEs FIRST arcsecond of declination (J2000)
31- 37 F7.2 mJy F20cm FIRST catalog peak 20cm flux density
39- 43 F5.2 mag u'mag SDSS-DR5 u' band magnitude
45- 49 F5.2 mag g'mag SDSS-DR5 g' band magnitude
51- 55 F5.2 mag r'mag SDSS-DR5 r' band magnitude
57- 61 F5.2 mag i'mag SDSS-DR5 i' band magnitude
63- 67 F5.2 mag Jmag 2MASS J band magnitude
69- 73 F5.2 mag Ksmag 2MASS Ks band magnitude
75- 78 F4.2 mag r'-Ks The r'-Ks color index
80- 83 F4.2 mag J-Ks The J-Ks color index
85- 90 A6 --- Spec Observatory where the spectrum was obtained (1)
92- 98 A7 --- OType Spectroscopic object type
100-105 F6.4 --- z ? Redshift
107-139 A33 --- Comm Comments
141-154 A14 --- Ref References code; see refs.dat file
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Note (1): Abbreviations as follows:
ESI = ESI instrument at the 10m Keck telescope, at a spectral resolution of
∼1.25Å.
KAST = KAST spectrograph on the Shane 3m telescope at the Lick observatory,
at a spectral resolution of ∼2.35Å.
LRIS = Low Resolution Imaging Spectrometer (LRIS) instrument on the Keck 10m
telescope
Liter. = Spectroscopy from literature
NOT = ALFOSC spectrograph on the 2.5m Nordic Optical Telescope (NOT)
SDSS = Spectra from SDSS
SOAR = Goodman Spectrograph on the 4.1m SOAR telescope
Spex = near-IR spectra from the Spex instrument on the Infrared Telescope
Facility 3m telescope
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [F2MS]
5- 13 A9 --- F2MS Quasar identification
15- 19 F5.3 --- z Redshift
21- 24 F4.2 mag E(B-V) Reddening
26- 29 F4.2 mag e_E(B-V) E(B-V) uncertainty
31- 34 I4 km/s WHb ? Hβ width
35 A1 --- f_WHb [*] peculiar Hβ lines (1)
37- 39 I3 km/s e_WHb ? WHb uncertainty
41- 46 F6.2 mag iMAG Absolute i band magnitude
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Note (1):
* = F2MS1618+3502 and F2MS1656+3821 showed broad lines in their spectra
in the near-IR and these were therefore classified as Type 1 quasars
whereas their Hβ line are not broader than 1000km/s.
See section 2.2 for further details.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- --- [F2MS]
5- 13 A9 --- F2MS Quasar identification
15- 19 F5.3 --- z Redshift
21- 25 I5 --- Baln ?=0 MgII line balnicity (see "f_Baln" column)
26 A1 --- f_Baln [a] Baln derived from CIV (1)
28- 32 I5 --- Abs ?=0 MgII line absorption index (see "f_Abs")
otherwise flagged
33 A1 --- f_Abs [a] Abs derived from CIV (1)
35- 42 F8.3 --- Chi2 ? χ2 fit
44- 71 A28 --- OType Object type (2)
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Note (1): 'a' indicates CIV derived Balnicities and Absorption Index, all
other are for the MgII line, which in most cases had much higher
signal-to-noise ratio in the spectra.
Note (2): Obect types:
BAL = Broad absorption line quasar (BAL quasar)
LoBAL = Low-ionization BAL (showing broad absorption troughs in the MgII
line)
FeLoBAL = FeII low-ionization BAL (with absorption troughs in the
metastable FeII line)
HiBAL = only show prominent absorption troughs in the high-ionization
lines such as CIV
Mini-BAL = Object that would have been rejected as a BAL by Weymann et al.
(1991ApJ...373...23W 1991ApJ...373...23W) since the absorption troughs were either
too narrow (below 2000km/s, but above 1000km/s), or because they
were so close to the emission redshift and could have been
mistaken with absorbers associated with the host galaxy (although
most host galaxies do not have such large velocity dispersions).
We, yet, include them in the discussion about BALs.
See section 3.2 for further details.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Ref Code reference
7- 25 A19 --- BibCode Bibcode
27- 47 A21 --- Aut Author's reference
49- 88 A40 --- Note VizieR catalog reference
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History:
From electronic version of the journal
References:
Glikman et al. Paper I. 2007ApJ...667..673G 2007ApJ...667..673G Cat. J/ApJ/667/673
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 10-Jun-2011