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J/ApJ/849/53      Composite SEDs of type 1 and type 2 QSOs      (Hickox+, 2017)

Composite spectral energy distributions and infrared-optical colors of type 1 and type 2 quasars. Hickox R.C., Myers A.D., Greene J.E., Hainline K.N., Zakamska N.L., DiPompeo M.A. <Astrophys. J., 849, 53 (2017)> =2017ApJ...849...53H
ADC_Keywords: QSOs; Energy distributions; Surveys Keywords: galaxies: active ; infrared: galaxies ; quasars: general ; surveys Abstract: We present observed mid-infrared and optical colors and composite spectral energy distributions (SEDs) of type 1 (broad-line) and 2 (narrow-line) quasars selected from Sloan Digital Sky Survey (SDSS) spectroscopy. A significant fraction of powerful quasars are obscured by dust and are difficult to detect in optical photometric or spectroscopic surveys. However, these may be more easily identified on the basis of mid-infrared (MIR) colors and SEDs. Using samples of SDSS type 1 and 2 matched in redshift and [OIII] luminosity, we produce composite rest-frame 0.2-15µm SEDs based on SDSS, UKIDSS, and Wide-field Infrared Survey Explorer photometry and perform model fits using simple galaxy and quasar SED templates. The SEDs of type 1 and 2 quasars are remarkably similar, with the differences explained primarily by the extinction of the quasar component in the type 2 systems. For both types of quasar, the flux of the active galactic nucleus (AGN) relative to the host galaxy increases with AGN luminosity (L[OIII]) and redder observed MIR color, but we find only weak dependencies of the composite SEDs on mechanical jet power as determined through radio luminosity. We conclude that luminous quasars can be effectively selected using simple MIR color criteria similar to those identified previously (W1-W2>0.7; Vega), although these criteria miss many heavily obscured objects. Obscured quasars can be further identified based on optical-IR colors (for example, (u-W3[AB]>1.4(W1-W2[Vega])+3.2). These results illustrate the power of large statistical studies of obscured quasars selected on the basis of MIR and optical photometry. Description: We employ two samples of quasars selected from the spectroscopic database of SDSS. The first sample (QSO 1s) consists of broad-line (type 1) quasars selected for spectroscopy based on their blue optical-UV colors. These objects are spectroscopically confirmed to have broad permitted emission lines indicative of gas moving in the gravitational potential of a BH. The other sample consists of obscured, narrow-line (type 2) QSOs. These were targeted by SDSS based on unusual colors or detections at X-ray or radio wavelengths but were then spectroscopically selected to have luminous emission in the [OIII]λ5007 emission line. Broad-line objects were selected from the SDSS catalog of Shen+ (2011, J/ApJS/194/45). The type 2 quasars (QSO 2s) were taken from Reyes+ (2008, J/AJ/136/2373) and Yuan+ (2016MNRAS.462.1603Y), which expand the original search of Zakamska+ (2003, J/AJ/126/2125). See section 2 for further details. We use a simple procedure to construct a mean SED for each of the two populations. We include only sources with detections in all 12 SDSS, UKIDSS, and WISE bands, as described in Section 3, which represents 334 QSO 1s and 406 QSO 2s, respectively. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 32 78 *Composite QSO 1 and 2 SEDS
Note on table1.dat: The composite SEDs presented here are for the primary sample using SDSS, UKIDSS, and WISE photometry, produced as described in Section 4 and as shown in Figure 2.
See also: II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003) II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009) II/312 : GALEX-DR5 (GR5) sources from AIS and MIS (Bianchi+ 2011) II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012) VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998) VII/241 : The 2dF QSO Redshift Survey (Croom+ 2004) VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006) V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012) II/328 : AllWISE Data Release (Cutri+ 2013) VIII/92 : The FIRST Survey Catalog, Version 2014Dec17 (Helfand+ 2015) J/ApJS/95/1 : Atlas of Quasar Energy Distributions (Elvis+ 1994) J/AJ/126/2125 : SDSS candidate type II quasars (Zakamska+, 2003) J/AJ/128/1002 : SDSS candidate type II quasars. II (Zakamska+, 2004) J/ApJ/640/167 : AGNs and ULIRGs in the CDF-South (Alonso-Herrero+, 2006) J/ApJ/642/673 : IR-selected obscured AGN candidates (Polletta+, 2006) J/A+A/457/517 : ATESP 5 GHz radio survey. I. (Prandoni+, 2006) J/ApJS/166/470 : SDSS-Spitzer type I QSOs IR photometry (Richards+, 2006) J/ApJ/654/115 : DEEP2 Galaxy Redshift Survey: SDSS QSOs (Coil+, 2007) J/AJ/133/2222 : Clustering of high-redshift QSOs from SDSS (Shen+, 2007) J/ApJ/658/815 : Radio loudness of active galactic nuclei (Sikora+, 2007) J/AJ/136/2373 : Type 2 quasars from SDSS (Reyes+, 2008) J/ApJS/180/67 : Photometric selection of QSOs from SDSS. II. (Richards+, 2009) J/ApJ/713/970 : Low-resolution SED templates for AGNs & gal. (Assef+, 2010) J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011) J/ApJ/751/52 : AGN cand. from the WISE, 2MASS, RASS (W2R) (Edelson+, 2012) J/ApJ/754/45 : IR properties of Swift/BAT X-ray AGNs (Ichikawa+, 2012) J/ApJ/757/13 : IR SEDs of 24um z∼0.3-3 galaxies (Sajina+, 2012) J/ApJ/772/26 : AGN with WISE. II. The NDWFS Bootes field (Assef+, 2013) J/ApJS/208/24 : Spitzer MIR AGN survey. I. (Lacy+, 2013) J/ApJ/790/54 : AGN models according to a UV to Mid-IR study (Chung+, 2014) J/ApJ/791/113 : MIR-selected quasar parameters (Dai+, 2014) J/ApJ/804/27 : NIR photometry of hot dust-obscured galaxies (Assef+, 2015) J/ApJS/221/12 : AGNs in the MIR using AllWISE data (Secrest+, 2015) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 6 F6.3 [um] logWave [-0.7/1.3] Log wavelength 8- 13 F6.3 [-] logSED1 [-1.5/0.5] Log scaled Fν for QSO 1 15- 19 F5.3 [-] e_logSED1 [0.02/0.3] Dispersion in logSED1 21- 26 F6.3 [-] logSED2 [-2.7/0.6] Log scaled Fν for QSO 2 28- 32 F5.3 [-] e_logSED2 [0.03/0.4] Dispersion in logSED2
History: From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 14-Jun-2018
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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