QSO1993 (G6): 1993 Hewitt & Burbidge Catalog of QSOs (19940303)
FILE: qso1993.g6 (7315 quasars)
CONTENTS: 1993 Hewitt & Burbidge Catalog of Quasi-Stellar Objects
DATASET: This file comes in HyperSky dataset G-16, version 19940303. Availability on HyperSky CD-ROM: Vol. 2 (1995)
NOTE! This catalog is the update of the 1989 version of the Hewitt & Burbidge catalog in HyperSky catalog set G-12.
DESCRIPTION: This datafile contains a total of 7315 quasars from the REVISED AND UPDATED CATALOG OF QUASI-STELLAR OBJECTS, by Hewitt and Burbidge (1993). The catalog is an update of the third (1989) edition of the catalog, and contains "all known quasi-stellar objects (QSOs) with measured emission redshifts, and BL Lac objects, complete to 1992 December 31." In creating this version of the catalog, the authors have rigorously adhered to their definition of a QSO as a starlike object (with or without fuzz) which has a redshift z >= 0.1. Consequently a few objects from previous catalogs with z < 0.1 have been dropped. Also missing from the catalog are 22 quasars, many with high redshifts, whose positions were not provided to the authors.
Because this catalog is a collection and not a uniform survey, HyperSky users will note that the distribution of quasars is highly irregular. In particular, distinct concentrations will appear in various areas. These reflect the results of specific surveys carried out at various times by various groups. A dramatic example of this is a "line" of quasars centered at RA 12h 15m, Declination -11.3 degrees, which extends about 12 degrees at a constant declination. Likewise, in other areas users will find roughly square areas containing huge concentrations of quasars. Often such quasar concentrations will be coincident with galaxy clusters, apparently reflecting discoveries made during studies of those clusters.
The HyperSky catalog file is based on a machine-readable version of the catalog provided by sources at Caltech.
DATA: The HyperSky datafile contains the following data from the catalog:
POSITION: Right Ascension and Declination are the equinox 2000 values provided in the catalog.
MAG: the apparent visual magnitude, which can range from 13.0 to 23.4. Often the only magnitudes available to the authors were photographic magnitudes, B-magnitudes, or estimates from Schmidt plates. Hence these magnitudes are very uncertain and inhomogenous.
IDENTIFICATION: Designation in the IAU nomenclature system, consisting of the 1950 equinox hours and minutes of Right Ascension followed by decimal degrees of declination.
COMMENTS: The comment lines contain the following information, provided if available for each radio source identification:
* A line beginning with "ze=" giving the emission redshift. This may be followed on the same line by a string beginning with "za=" giving the absorption redshift.
* A line starting with an "=" sign, giving one alternate name of the quasars in various catalogs. This is generally the name under which the object was first identified. Most such names will have the general form "XXX nnn" where XXX is the catalog name abbreviation, and nnn is the catalog number or id. Some catalog references contain only a catalog name abbreviation (eg, "PKS"). The inference in such cases is that the catalog identification is identical to the IAU identification described above.
* A subset of the available notes. A number of comments were encoded into the notes using short strings, and have been expanded here for clarity. One or more of the following comments may appear for any given quasar:
21 cm absorption
broad absorption line QSO
broad absorption lines variable
broad absorption lines questionable
emission line variable
high polarization
infrared variable
infrared / radio source
infrared polarization
IRAS source
jet
many Fe II lines
millimeter wave variable
narrow emission lines
not detected in ultraviolet
not detected as radio source
not detected as X-ray source
optical jet or fuzz reported
optical polarization
optical violent variable
radio jet
radio polarization
spectral variability
ultraviolet absorption
ultraviolet emission
ultraviolet variable
variability not detected
X-ray variable
In the original catalog, a numbered reference was associated with each such encoded comment. These have been dropped in the HyperSky datafile. Interested users are referred to the original catalog in the reference below.
REFERENCE: The ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 87:451-947, August 1993