ROMABZCAT - Roma-BZCAT Multi-Frequency Catalog of Blazars
The Roma-BZCAT is structured in two parts. Part 1, at present the only one available on-line, contains the lists of blazars, which are classified in three main groups, according to their spectral properties. Each blazar is identified by a three-letter code, where the first two letters are BZ for blazar and the third one specifies the type, followed by the truncated equatorial coordinates (J2000).
This version of the Roma-BZCAT is Version 4.1.1 (2012 August).
Roma-BZCAT: a multifrequency catalogue of blazars. Massaro E., Giommi P., Leto C., Marchegiani P., Maselli A., Perri M., Piranomonte S., Sclavi S. <Astron. Astrophys., 495, 691-696 (2009)> =2009A&A...495..691M
A uniquely identifying source number for each blazar in the catalog, mostly in order of increasing J2000.0 Right Ascension (source numbers 3144-3149 are actually the first 6 blazars in RA, followed by source numbers 1-3143).
The Roma-BZCAT source designation, e.g., '[MGL2009] BZt JHHMM.m+DDMM' where 't' can be 'B', 'Q' or 'U' depending on the blazar sub-type: BL Lacertae object or candidate, flat spectrum radio quasars or a blazar of uncertain/transitional type, respectively, and the numbers are the J2000.0 equatorial coordinates of the blazar.
The Right Ascension of the blazar in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.1 seconds of time in the original table.
The Declination of the blazar in the selected equinox. This was given in J2000.0 equatorial coordinates to a precision of 0.1 arcseconds in the original table.
The Galactic Longitude of the blazar.
The Galactic Latitude of the blazar.
The redshift of the blazar.
A flag parameter for the redshift indicating uncertainty in the value ('?'), extreme uncertainty ('??') or a lower limit ('>').
The R-band magnitude of the blazar, taken from the USNO-B1 Catalog.
The blazar sub-type classification:
BZB = BL Lac objects, used for AGNs with a featureless optical spectrum or only with absorption lines of galaxian origin and weak and narrow emission lines; BZ? = BL Lac candidates; BZQ = flat-spectrum radio quasars, with an optical spectrum showing broad emission lines and dominant blazar characteristics; BZU = blazars of uncertain type, adopted for sources with peculiar characteristics but also showing blazar activity: for instance, occasional presence/absence of broad spectral lines or features, transition objects between a radio galaxy and a BL Lac, galaxies hosting a low luminosity blazar nucleus, etc.;
The radio flux density of the blazar at 1.4GHz (from NVSS or SUMSS), in mJy: if the 1.4-GHz flux density is unknown, the flux density at another radio frequency is given.
The radio flux density of the blazar at 143 GHz, in mJy.
The X-ray flux of the blazar in the 0.1-2.4 keV band, mostly taken from the ROSAT Archive, in erg cm-2 s-1.
The gamma-ray flux of the blazar in the 1-100 GeV band, taken from Fermi, in photons cm-2 s-1.