ACDS V10.0 - Detailed Description of J/ApJS/234/23

ACDS V10.0 - Sun Jan 19 12:31:47 CET 2025

| # Detailed Description of J/ApJS/234/23 : The WISE AGN candidates catalogs (Assef+, 2018) |

Note : this is the description file of the original catalog. This HTML page corresponds well to the original description, but some minor changes in the format may have been introduced in the FITS output files in order to allow for arithmetic operations on quantities such as coordinates and times. h:m:s and d:m:s units are normally converted into degrees, and YYYY-MM-DD into julian days.
Similarly, some slight changes may have been introduced in the units; the value given in the HTML files supersedes the value indicated in the ReadMe file for this catalogue.

    J/ApJS/234/23          The WISE AGN candidates catalogs          (Assef+, 2018)
    ================================================================================
    The WISE AGN catalog.
        Assef R.J., Stern D., Noirot G., Jun H.D., Cutri R.M., Eisenhardt P.R.M.
       <Astrophys. J. Suppl. Ser., 234, 23-23 (2018)>
       =2018ApJS..234...23A    (SIMBAD/NED BibCode)
    ================================================================================
    ADC_Keywords: Photometry, infrared ; Active gal. nuclei

    Keywords: galaxies: active; infrared: general; quasars: general

    Abstract:
        We present two large catalogs of active galactic nucleus (AGN)
        candidates identified across 30,093deg2 of extragalactic sky from
        the Wide-field Infrared Survey Explorer's AllWISE Data Release. Both
        catalogs are selected purely using the Wide-field Infrared Survey
        Explorer (WISE) W1 and W2 bands. The R90 catalog consists of 4,543,530
        AGN candidates with 90% reliability, while the C75 catalog consists of
        20,907,127 AGN candidates with 75% completeness. These reliability and
        completeness figures were determined from a detailed analysis of UV-
        to near-IR spectral energy distributions of ~105 sources in the
        9deg2 Bootes field. The AGN selection criteria are based on those of
        Assef+ (2013, J/ApJ/772/26) recalibrated to the AllWISE data release.
        We provide a detailed discussion of potential artifacts and excise
        portions of the sky close to the Galactic Center, Galactic Plane,
        nearby galaxies, and other expected contaminating sources. These
        catalogs are expected to enable a broad range of science, and we
        present a few illustrative cases. From the R90 sample, we identify 45
        highly variable AGNs lacking radio counterparts in the FIRST survey.
        One of these sources, WISEA J142846.71+172353.1, is a changing-look
        quasar at z=0.104, which has changed from having broad H{alpha} to
        being a narrow-lined AGN. We characterize our catalogs by comparing
        them to large, wide-area AGN catalogs in the literature. We identify
        four ROSAT X-ray sources that are each matched to three WISE-selected
        AGNs in the R90 sample within 30". Spectroscopy reveals that one of
        these systems, 2RXS J150158.6+691029, consists of a triplet of quasars
        at z=1.133±0.004, suggestive of a rich group or forming galaxy
        cluster.

    File Summary:

           FileName      Lrecl  Records   Explanations

    ×                   80        .   This file
    × ReadMe            80        .   This file
    × r90cat.dat       106  4543530   R90 final AGN candidates catalog (table 1)
    × c75cat.dat       106 20907127   C75 final AGN candidates catalog (table 2)
    × r90ex.dat        106    20645   R90 catalog of extended sources (table 7)
    × c75ex.dat        106    26331   C75 catalog of extended sources (table 8)

    Description of file: Original FITS files for R90 (AGN candidates
      with 90% reliability) and C75 (AGN candidates with 75% completeness) final
      and extended catalogs are available in the FTP section.

    See also:
     VII/7          : Lynds' Catalogue of Dark Nebulae (LDN) (Lynds 1962)
     VII/9          : Lynds' Catalogue of Bright Nebulae (Lynds 1965)
     VIII/65        : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
     VII/233        : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
     II/311         : WISE All-Sky Data Release (Cutri+ 2012)
     II/328         : AllWISE Data Release (Cutri+ 2013)
     V/147          : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
     VII/279        : SDSS quasar catalog: twelfth data release (Paris+, 2017)
     J/A+AS/70/95   : Warm IRAS sources. I. AGN candidates (de Grijp+ 1987)
     J/AJ/131/666   : Double-lobed radio quasars from the SDSS (de Vries+, 2006)
     J/AJ/133/186   : Opt. spectroscopy of 77 luminous AGNs and QSOs (Lacy+, 2007)
     J/ApJ/684/905  : z>1 gal. clusters from IRAC Shallow Survey (Eisenhardt+, 2008)
     J/ApJ/701/428  : The Spitzer Deep, Wide-Field Survey (SDWFS) (Ashby+, 2009)
     J/ApJ/696/870  : Catalina Real-time Transient Survey (CRTS) (Drake+, 2009)
     J/ApJS/185/433 : SWIRE/Chandra survey in Lockman Hole Field (Wilkes+, 2009)
     J/ApJ/713/970  : Low-resolution SED templates for AGNs & gal. (Assef+, 2010)
     J/ApJ/708/584  : SEXSI Spitzer catalog (Eckart+, 2010)
     J/ApJ/751/52   : AGN cand. from the WISE, 2MASS, RASS (W2R) (Edelson+, 2012)
     J/ApJS/200/8   : AGES: the AGN and Galaxy Evolution Survey (Kochanek+, 2012)
     J/ApJS/199/3   : The quasars MMT-BOSS pilot survey (Ross+, 2012)
     J/AJ/144/49    : Quasars from SDSS-DR7, WISE and UKIDSS surveys (Wu+, 2012)
     J/ApJ/772/26   : AGN with WISE. II. The NDWFS Bootes field (Assef+, 2013)
     J/AJ/145/101   : Updated nearby galaxy catalog (Karachentsev+, 2013)
     J/ApJS/208/24  : Spitzer MIR AGN survey. I. (Lacy+, 2013)
     J/MNRAS/438/1149 : WISE data for radio-loud AGN samples (Gurkan+, 2014)
     J/ApJS/212/1   : The WISE catalog of Galactic HII regions (Anderson+, 2014)
     J/ApJ/790/54   : AGN models according to a UV to Mid-IR study (Chung+, 2014)
     J/ApJ/792/30   : NEOWISE magnitudes for near-Earth objects (Mainzer+, 2014)
     J/ApJS/221/12  : AGNs in the MIR using AllWISE data (Secrest+, 2015)
     J/A+A/588/A103 : 2nd ROSAT all-sky survey (2RXS) source catalog (Boller+, 2016)
     J/MNRAS/473/4937 : AllWISE xid for ROSAT/2RXS & XMMSLEW2 (Salvato+, 2018)
     http://www.sao.ru/lv/lvgdb/ : Online catalog of the Local Volume galaxies

    Byte-by-byte Description of file:  *.dat

       Bytes Format Units   Label     Explanations

       1- 19  A19   ---     WISEA     AllWISE designation (JHHMMSS.ss+DDMMSS.s)
      21- 31  F11.7 deg     RAdeg     Right ascension (J2000)
      33- 43  F11.7 deg     DEdeg     Declination (J2000)
      45- 50  F6.3  mag     W1mag     [8/21.7] WISE W1 (3.4um) magnitude
      52- 57  F6.3  mag     e_W1mag   [0.01/0.6]?=- W1mag uncertainty
      59- 64  F6.3  mag     W2mag     [7/17.7] WISE W2 (4.2um) magnitude
      66- 71  F6.3  mag     e_W2mag   [0.008/0.3] W2mag uncertainty
      73- 78  F6.3  mag     W3mag     [1.2/17.3]?=- WISE W3 (12um) magnitude
      80- 85  F6.3  mag     e_W3mag   [0.006/0.6]?=- W3mag uncertainty
      87- 92  F6.3  mag     W4mag     [-3.2/10.5]?=- WISE W4 (22um) magnitude
      94- 99  F6.3  mag     e_W4mag   [0.003/0.6]?=- W4mag uncertainty
         101  I1    ---     MS        [0/1] Moon-SAA flag (1)
     103-106  I4    deg-2   SigPix    [5/2497]? {Sigma}pix value;
                                       only for the final catalogs (2)

    Note (1): We strongly caution the user when considering faint sources near the
      south Atlantic anomaly (SAA) in fields with high Moon background. To aid in
      identifying possibly problematic sources, we have added a MOON_SAA flag to
      the catalog, which is equal to 1 if the source is at a declination between
      -15° and -45°, consistent with the SAA latitude, has a moon_lev flag
      in W2 equal or greater to 3, and W2 S/N<=7.
      See section 3.3.2. for further explanations.
    Note (2): We find a number of spurious sources associated with residuals left
              by solar system planets in the co-added WISE data.
              We include for each source in the final R90 and C75 catalogs the
              surface density of the HEALPix pixel that contains it ({Sigma}pix)
              so the user can decide how to best deal with the artifacts described
              in section 3.3.4.

    History:
        From electronic version of the journal (FITS files)
    ================================================================================
    (End)                                     Emmanuelle Perret [CDS]    19-Mar-2018