J/ApJ/755/167 Low-mass black holes in SDSS Seyfert 1 galaxies (Dong+, 2012)
A uniformly selected sample of low-mass black holes in Seyfert 1 galaxies.
Dong X.-B., Ho L.C., Yuan W., Wang T.-G., Fan X., Zhou H., Jiang N.
<Astrophys. J., 755, 167 (2012)>
=2012ApJ...755..167D 2012ApJ...755..167D
ADC_Keywords: Active gal. nuclei ; Spectroscopy ; Photometry, SDSS
Keywords: galaxies: active; galaxies: nuclei; galaxies: Seyfert
Abstract:
We have conducted a systematic search of low-mass black holes (BHs) in
active galactic nuclei (AGNs) with broad Hα emission lines,
aiming at building a homogeneous sample that is more complete than
previous ones for fainter, less highly accreting sources. For this
purpose, we developed a set of elaborate, automated selection
procedures and applied it uniformly to the Fourth Data Release of the
Sloan Digital Sky Survey. Special attention is given to AGN-galaxy
spectral decomposition and emission-line deblending. We define a
sample of 309 type 1 AGNs with BH masses in the range
8x104-2x106M☉ (with a median of 1.2x106M☉), using
the virial mass estimator based on the broad Hα line. About half
of our sample of low-mass BHs differs from that of Greene & Ho (2007,
Cat. J/ApJ/670/92), with 61 of them discovered here for the first
time. Our new sample picks up more AGNs with low accretion rates: the
Eddington ratios of the present sample range from ≲0.01 to ∼1, with
30% below 0.1. This suggests that a significant fraction of low-mass
BHs in the local universe are accreting at low rates. The host
galaxies of the low-mass BHs have luminosities similar to those of L*
field galaxies, optical colors of Sbc spirals, and stellar spectral
features consistent with a continuous star formation history with a
mean stellar age of less than 1Gyr.
Description:
In this paper we present a sample of 309 (drawn from a parent sample
of 8862 sources at z<0.35) Seyfert 1 galaxies hosting a central black
hole of MBH<2x106M☉, uniformly selected from the Fourth
Data Release (DR4; Adelman-McCarthy et al. 2006, Cat. II/267;
superseded by Cat. II/294) of the SDSS. The spectra from the SDSS
spectrographs are flux- and wavelength-calibrated, with 4096 pixels
from 3800 to 9200Å at a resolution R=λ/Δλ∼1800.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 46 309 The SDSS sample
table2.dat 103 309 Emission-line measurements
table3.dat 39 309 Luminosity and mass measurements
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See also:
II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)
J/A+A/549/A119 : Black-hole masses of type-1 AGNs (Caccianiga+, 2013)
J/ApJS/194/42 : SDSS-DR3 MgII-based black hole masses (Rafiee+, 2011)
J/ApJ/742/68 : HST observations of low-mass BH host galaxies (Jiang+, 2011)
J/ApJ/711/284 : Galaxy Zoo: AGN host galaxies (Schawinski+, 2010)
J/MNRAS/407/2399 : AGN activity and black hole mass (McKernan+, 2010)
J/ApJ/702/441 : Obscured active galaxies (Greene+, 2009)
J/ApJ/699/800 : Mass functions of active black holes (Vestergaard+, 2009)
J/ApJ/699/453 : Determination of black hole masses (Shaposhnikov+, 2009)
J/ApJ/692/856 : Supermassive black holes masses upper limits (Beifiori+, 2009)
J/ApJ/690/20 : Models of the AGN and black hole populations (Shankar+, 2009)
J/ApJ/680/169 : SDSS DR5 virial black hole masses (Shen+, 2008)
J/ApJ/670/92 : New sample of low-mass black holes in AGN (Greene+, 2007)
J/ApJ/667/131 : Mass function of active black holes (Greene+, 2007)
J/ApJS/168/1 : Black hole mass estimates (Kelly+, 2007)
J/ApJ/641/L21 : BH mass and velocity dispersion relation (Greene+, 2006)
J/ApJ/614/91 : Black hole mass and accretion rate of AGNs (Wu+, 2004)
J/ApJ/596/437 : Stellar-mass black holes in the SDSS (Chisholm+, 2003)
http://www.sdss.org/ : SDSS home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/309] Identifier from this paper
5- 23 A19 --- SDSS Official SDSS-DR4 name (JHHMMSS.ss+DDMMSS.s)
25- 30 F6.4 --- z [0.005/0.4] SDSS pipeline redshift
32- 36 F5.2 mag gmag [13.4/21.4] Petrosian SDSS g band magnitude (1)
38- 41 F4.2 mag g-r [0.01/1.1] Petrosian SDSS (g-r) color index
43- 46 F4.2 mag Ag [0.02/1.1] Galactic extinction in the g band
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Note (1): Uncorrected for Galactic extinction.
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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- 3 I3 --- Seq [1/309] Identifier from this paper
5 A1 --- l_[3727] The 3σ upper limit flag on [3727]
6- 11 F6.2 [mW/m2] [3727] ? Log of [OII] (3727Å) flux (2)
13 A1 --- l_[4570] The 3σ upper limit flag on [4570]
14- 19 F6.2 [mW/m2] [4570] Log of FeII (4570Å) flux (2)
21 A1 --- l_[Hb]n The 3σ upper limit flag on [Hb]n
22- 27 F6.2 [mW/m2] [Hb]n Log of narrow Hβ flux (2)
29 A1 --- l_[Hb]b The 3σ upper limit flag on [Hb]b
30- 35 F6.2 [mW/m2] [Hb]b ? Log of broad Hβ flux (2)
37- 42 F6.2 [mW/m2] [5007] Log of [OIII] (5007Å) flux (2)
44 A1 --- l_[5007] The 3σ upper limit flag on [5007]
45- 50 F6.2 [mW/m2] [6300] ? Log of [OI] (6300Å) flux (2)
52 A1 --- l_[Ha]n The 3σ upper limit flag on [Ha]n
53- 58 F6.2 [mW/m2] [Ha]n Log of narrow Hα flux (2)
60- 65 F6.2 [mW/m2] [Ha]b Log of broad Hα flux (2)
67 A1 --- l_[6583] The 3σ upper limit flag on [6583]
68- 73 F6.2 [mW/m2] [6583] ? Log of [NII] (6583Å) flux (2)
75 A1 --- l_[6716] The 3σ upper limit flag on [6716]
76- 81 F6.2 [mW/m2] [6716] ? Log of [SII] (6716Å) flux (2)
83 A1 --- l_[6731] The 3σ upper limit flag on [6731]
84- 89 F6.2 [mW/m2] [6731] ? Log of [SII] (6731Å) flux (2)
91- 94 I4 km/s W(Ha) [486/2382] FWHM of broad Hα line (3)
96- 98 I3 km/s W(5007) [85/800]? FWHM of [OIII] (5007Å) line (3)
100-103 I4 km/s W(6731) [70/450]? FWHM of [SII] (6731Å) line (3)
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Note (2): These are observed values; no NLR or BLR extinction correction has
been applied.
Note (3): Calculated from the best-fit models and have been corrected for
instrumental broadening using the values measured from arc spectra
and tabulated by the SDSS.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/309] Identifier from this paper
5- 10 F6.2 mag gMag [-22.4/-17.4] Total SDSS g-band absolute magnitude
12- 17 F6.2 mag gMagA [-20.6/-12.3] AGN SDSS g-band absolute
magnitude (4)
19- 24 F6.2 mag gMagh [-22.2/-15.9] Host galaxy SDSS g-band absolute
magnitude (5)
26- 30 F5.2 [10-7W] logLHa Log broad Hα luminosity (log(erg/s))
32- 34 F3.1 [Msun] logM [4.9/6.3] Log virial blackhole mass
36- 39 F4.1 [-] logL [-2.4/0.3] Log of Eddington ratio
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Note (4): Estimated from LogLHa and a conversion from LHα to gMag
assuming fλ∝λ-1.56.
Note (5): Obtained by subtracting the AGN luminosity from the total luminosity.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 12-Mar-2014