J/ApJ/713/970 Low-resolution SED templates for AGNs and galaxies (Assef+, 2010)
Low-resolution spectral templates for active galactic nuclei and galaxies from
0.03 to 30 µm.
Assef R.J., Kochanek C.S., Brodwin M., Cool R., Forman W., Gonzalez A.H.,
Hickox R.C., Jones C., Le Floc'h E., Moustakas J., Murray S.S., Stern D.
<Astrophys. J., 713, 970-985 (2010)>
=2010ApJ...713..970A 2010ApJ...713..970A
ADC_Keywords: Energy distributions ; Active gal. nuclei ; Galaxies, photometry ;
Magnitudes, absolute ; Redshifts
Keywords: galaxies: active - galaxies: distances and redshifts -
galaxies: photometry - quasars: general
Abstract:
We present a set of low-resolution empirical spectral energy
distribution (SED) templates for active galactic nuclei (AGNs) and
galaxies in the wavelength range from 0.03um to 30um based on the
multi-wavelength photometric observations of the NOAO Deep-Wide Field
Survey Bootes field and the spectroscopic observations of the AGN and
Galaxy Evolution Survey. Our training sample is comprised of 14448
galaxies in the redshift range 0≲z≲1 and 5347 likely AGNs in the
range 0≲z≲5.58. The galaxy templates correspond to the SED templates
presented in 2008 by Assef et al. (Cat. J/ApJ/676/286) extended into
the UV and mid-IR by the addition of FUV and NUV GALEX and MIPS 24um
data for the field. We use our templates to determine photometric
redshifts for galaxies and AGNs. While they are relatively accurate
for galaxies (σz/(1+z)=0.04, with 5% outlier rejection), their
accuracies for AGNs are a strong function of the luminosity ratio
between the AGN and galaxy components. Somewhat surprisingly, the
relative luminosities of the AGN and its host are well determined even
when the photometric redshift is significantly in error. Finally, we
use our templates to predict the color-color distribution of sources
in the upcoming Wide-Field Infrared Survey Explorer (WISE) mission and
define a color criterion to select AGNs analogous to those developed
for IRAC photometry. We estimate that in between 640000 and 1700000
AGNs will be identified by these criteria, but without additional
information, WISE-selected quasars will have serious completeness
problems for z≳3.4.
Description:
The data used in this work are an expansion over that of Assef et al.
(2008, Cat. J/ApJ/676/286). It is based on the extensive
multi-wavelength imaging of the NDWFS (Jannuzi & Dey
1999ASPC..191..111J 1999ASPC..191..111J) Bootes field and the spectroscopic observations
of the same field by the AGES (C. S. Kochanek et al.
2011arXiv1110.4371K 2011arXiv1110.4371K). NDWFS is a deep optical and near-infrared survey
that covers two 9.3deg2 regions of the sky, the Bootes and Cetus
fields. We focus on the Bootes field, which was imaged in BW
(3500-4750Å, peak at ∼4000Å), R, I, and K passbands to depths of
approximately 26.5, 26, 25.5, and 21 AB magnitudes (5σ, 2"
diameter aperture).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 61 300 SED templates
table2.dat 181 2404 SED templates absolute magnitudes
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See also:
VIII/62 : The Westerbork Northern Sky Survey (Leiden, 1998)
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
J/ApJ/716/530 : Mid-IR variability from the SDWFS (Kozlowski+, 2010)
J/ApJ/676/286 : Spectral templates for galaxies from 0.2 to 10um (Assef+,
2008)
J/ApJ/639/816 : The FLAMINGOS Extragalactic Survey (Elston+, 2006)
J/ApJS/166/470 : SDSS-Spitzer type I QSOs IR photometry (Richards+, 2006)
J/ApJ/641/140 : Optical counterparts in the NDWFS Bootes field (Brand+, 2006)
J/ApJ/634/L1 : 16µm sources in the NOAO Bootes field (Kasliwal+, 2005)
J/ApJS/161/9 : X-ray survey of the NDWFS Bootes field (Kenter+, 2005)
J/AJ/127/213 : LALA Bootes field X-ray source catalog (Wang+, 2004)
J/AJ/123/1784 : 1.4 GHz imaging of the Bootes field (de Vries+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 F7.4 um lambda [0.03/30] Wavelength (1)
9- 16 F8.4 10-14W/m2/Hz AGN Standard AGN template; 10-11erg/s/cm^2/Hz
18- 26 F9.4 10-17W/m2/Hz AGN2 AGN 2 template; 10-14erg/s/cm^2/Hz (2)
28- 37 F10.4 10-19W/m2/Hz E E galaxy template; 10-16erg/s/cm^2/Hz
39- 50 F12.4 10-20W/m2/Hz Sbc Sbc galaxy template; 10-17erg/s/cm^2/Hz
52- 61 F10.4 10-18W/m2/Hz Im Im galaxy template; 10-15erg/s/cm^2/Hz
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Note (1): All templates are normalized to be at a distance of 10pc and to
have an integrated luminosity between the wavelength boundaries of
1010L☉.
Note (2): Derived by using the Richards et al. (2006, Cat. J/ApJS/166/470)
SED as a starting point.
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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 F4.2 --- z Redshift
6 I1 --- Temp [1/4] Template number: 1=AGN, 2=E, 3=Sbc, 4=Im
8- 14 F7.3 mag NUVMag ?=99 GALEX NUV band absolute magnitude (2)
16- 22 F7.3 mag FUVMag ?=99 GALEX FUV band absolute magnitude (2)
24- 30 F7.3 mag BWMag BW band absolute magnitude (2)
32- 38 F7.3 mag BMag B band absolute magnitude (2)
40- 46 F7.3 mag VMag V band absolute magnitude (2)
48- 54 F7.3 mag RMag R band absolute magnitude (2)
56- 62 F7.3 mag IMag I band absolute magnitude (2)
64- 70 F7.3 mag zMag z band absolute magnitude (2)
72- 78 F7.3 mag JMag J band absolute magnitude (2)
80- 86 F7.3 mag HMag H band absolute magnitude (2)
88- 94 F7.3 mag KSMag KS band absolute magnitude (2)
96-102 F7.3 mag KMag K band absolute magnitude (2)
104-110 F7.3 mag 3.6Mag Spitzer/IRAC 3.6 micron band absolute magnitude (2)
112-118 F7.3 mag 4.5Mag Spitzer/IRAC 4.5 micron band absolute magnitude (2)
120-126 F7.3 mag 5.8Mag Spitzer/IRAC 5.8 micron band absolute magnitude (2)
128-134 F7.3 mag 8.0Mag Spitzer/IRAC 8.0 micron band absolute magnitude (2)
136-142 F7.3 mag 24Mag Spitzer/MIPS 24 micron band absolute magnitude (2)
144-150 F7.3 mag 3.4Mag WISE 3.4 micron band absolute magnitude (2)
152-158 F7.3 mag 4.6Mag WISE 4.6 micron band absolute magnitude (2)
160-166 F7.3 mag 12Mag WISE 12 micron band absolute magnitude (2)
168-174 F7.3 mag 22Mag WISE 22 micron band absolute magnitude (2)
176-181 F6.3 mag DM ? Distance modulus
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Note (2): Templates have been normalized to a "bolometric" luminosity of
1010L☉. The absolute magnitude we present here corresponds
to the canonical definition of the absolute magnitude (as in, for
example, eqn. 26 of Hogg 1999astro.ph..5116H 1999astro.ph..5116H) plus the K correction
term. This allows the calculation of photometric redshifts and K
corrections from the table. This is equivalent to Tables 3 and 4 of
Assef et al. 2008, Cat. J/ApJ/676/286 (see their caption for details).
All magnitudes are in the VEGA system except for NUV, FUV, z and the
WISE bands, which are in the AB system. Note that no template
incorporates IGM absorption and the AGN template is unreddened. For
calculating photometric redshifts and K-corrections allowing for
variable IGM absorption and obscuration of the AGN, public numerical
routines are provided on-line at
http://www.astronomy.ohio-state.edu/~rjassef/lrt.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 13-Apr-2012