CGRABS - Candidate Gamma-Ray Blazar Survey Source Catalog
The authors have constructed a uniform all-sky survey of bright blazars,
selected primarily by their flat radio spectra, that is designed to provide
a large catalog of likely gamma-ray active galactic nuclei (AGNs). The
defined sample, the Candidate Gamma-Ray Blazar Survey (CGRaBS) source
catalog, has 1625 targets with radio and X-ray properties similar to those
of the EGRET blazars, spread uniformly across the |b| > 10 degrees sky.
They also report progress toward optical characterization of the sample;
of objects with known red magnitude R < 23, 85% have been classified and 81%
have measured redshifts. One goal of this program is to focus attention on
the most interesting (e.g., high-redshift, high-luminosity, etc.) sources
for intensive multiwavelength study during the observations by the Large
Area Telescope (LAT) on the Gamma-Ray Large-Area Space Telescope (GLAST)
CGRaBS: An All-Sky Survey of Gamma-Ray Blazar Candidates
Healey, Stephen E.; Romani, Roger W.; Cotter, Garret; Michelson, Peter F.;
Schlafly, Edward F.; Readhead, Anthony C. S.; Giommi, Paolo; Chaty, Sylvain;
Grenier, Isabelle A.; Weintraub, Lawrence C.
=Astrophysical Journal Supplement Series, Volume 175, Issue 1, pp. 97-104.
This table was created by the HEASARC in April 2008 based on an
electronic version of Table 2 of the reference paper obtained from the
electronic ApJS web site.
This parameter is a unique name identifying CGRaBS sources using
the J2000.0 positional-based convention for names and the CGRaBS prefix,
as registered with the CDS Dictionary of Nomenclature of Celestial Objects.
The Right Ascension of the radio source in the selected equinox. This
was given in J2000 decimal degree coordinates and to a precision of 0.01
seconds of time in the original table.
The Declination of the radio source in the selected equinox. This
was given in J2000 decimal degree coordinates and to a precision of 0.1
arcseconds in the original table.
The Galactic Longitude of the radio source.
The Galactic Latitude of the radio source.
The flux density of the radio source at 8.4 GHz, in mJy.
The figure of merit (FoM) of the radio source, being
a measure of the combined probability that the radio source will be
similar to those blazar sources detected as EGRET gamma-ray sources.
This table contains only the best such sources having FoM > 0.04.
This parameter is discussed in some detail in Section 2 of the reference
This flag parameter is set to "X" to indicate that
the source would not satisfy the FoM cutoff if its X-ray flux were ignored
(see Section 2 of the reference paper).
This parameter is a limit flag for the R magnitude of the
optical counterpart to the radio source.
The R-band magnitude of the optical counterpart to the radio source.
The nominal Galactic extinction in the R band in the
direction of the radio source, derived from the Schlegel et al. (1998,
ApJ, 500, 525) maps.
The source classification, derived as discussed in
Section 3.2 of the reference paper, using the following abbreviations:
AGN - Active Galactic Nucleus (low-luminosity, broad-line blazar)
BLL - BL Lac (continuum-dominated blazar)
FSRQ - Flat spectrum radio quasar (luminous, broad-line blazar)
GALAXY- Source with small line equivalent widths but large H/K break contrast
NLRG - Narrow-line (< 1000 km/s) radio galaxy
PN - Planetary nebula
The redshift of the optical counterpart to the radio source.
This flag parameter is set to ':' to indicate that there is
some uncertainty in the quoted redshift value.
This parameter indicates the reference for the quoted
redshift, as follows:
V - Veron Quasar Catalog (12th Edition)
S - SDSS DR5 Quasar Catalog
N - NED
I - Simbad
C - CGRaBS spectroscopy
The HEASARC Browse object classification, based on the value of the
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