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1981A&AS...45..367Kuehr+
See also Kuerh's 79 catalog
Astron. Astrophys. Suppl. 45, 367 (1981)

Catalog of Extragalactic Radio Sources Having Flux Densities Greater Than 1 Jy at 5 GHz

Kuehr H., Witzel A., Pauliny-Toth I. I. K., and Nauber U.


ADC_Keywords: Galaxies, radio - 320; Galaxy catalogs - 330; Radio Sources - 685

Abstract

The catalog is a compilation of 518 extragalactic radio sources with flux densities greater than 1 Jy at 5 GHz. It contains sources from the NRAO-MPI 5-GHz Strong Source Surveys and from re-observation at 5 GHz of sources found in the Parkes 2.7-GHz surveys. All sources were found in 9.811 sr covered by the two surveys. This is essentially the whole sky, excluding the galactic plane (latitudes less than 10 degrees) and the Magellanic Clouds. The catalog includes radio flux densities, radio positions, object classes, visual magnitudes, redshifts, and spectral indices.

Introduction

Codes for the position references are listed in this document in the appendix. In the main file, errors are given for all radio positions, flux densities, spectral indices, and function coefficients. See the original paper for discussions of the completeness of the catalog, of the compilation of the flux density data, and of the fitting of simple analytic functions to the spectra.

The EGRS catalog lists information on 518 objects with one to sixteen flux density values for each source. The file header.dat lists the complete header information for each object. This line has been removed from catalog.dat. There are at most four density values in each record. Records containing fewer than four measurements are filled with blanks on the right. The first word of the file catalog.dat contains the id for the object.

refs.dat contains a numerically sorted list of the radio source catalogs cited in the flux density measurement records. For each source catalog the original reference or references (usually one, but in one case as many as three) are listed, as well as the pertinent characteristics of the catalog. When more than one line was needed for a reference up to four continuation lines were used.

File Summary:
--------------------------------------------------------------------
 FileName    Lrecl     Records     Explanation
--------------------------------------------------------------------
ReadMe        80         .         This file
header.dat   124       518         Details for each source
catalog.dat  129      2345         Catalog
refs.dat     124       187         References
--------------------------------------------------------------------
Byte-by-byte description of file: header.dat
------------------------------------------------------------------------------
Byte(s)   Format   Units    Label      Explanation
-----------------------------------------------------------------------------
  1-  8   A8       ---       id       *Source name
 10- 16   A7       ---       3C       *3C name
 18- 19   I2       h         RAh       Right Ascension (RA) (1950.0) hours
 20- 21   I2       min       RAm       RA (1950.0) minutes
 22- 26   F5.2     s         RAs       RA (1950.0) seconds
 27- 31   F5.2     s         e_RA      Error in RA
     33   A1       ---       DE-       Declination sign
 34- 35   I2       deg       DEd       Declination (DE) sign
 36- 37   I2       arcmin    DEm       DE minutes
 38- 41   F4.1     arcsec    DEs       DE seconds
 42- 46   F5.1     arcsec    e_DE      Error in DE
 48- 49   A2       ---       pos-ref  *Position reference
 50- 55   F6.1     deg       glat      Galactic latitude
 57- 59   A3       ---       cl       *Object class
 60- 64   F5.1     mag       mag      *?Visual magnitude
 65- 70   F6.3     km/s      rshift   *?Redshift
 71- 76   F6.2     ---       ind      *?Spectral index
 77- 80   F4.2     ---       e_ind     ?Sp. I. error
 82- 84   A3       ---       type     *Function type
 85- 91   F7.2     ---       A         ?Coefficient A
 92- 97   F6.2     ---       e_A       ?A error
 98-103   F6.2     ---       B         ?Coefficient B
104-107   F4.2     ---       e_B       ?B error
108-115   F8.2     ---       C         ?Coefficient C
116-121   F6.2     ---       e_C       ?C error
122-124   I3       ---       D         ?Coefficient D
--------------------------------------------------------------------------
Note on id:
The EGRS contains sources from the combined NRAO-MPI 5 GHz Strong Source Survey and Parkes 2.7 GHz Surveys. This is a coordinate-based naming system.
Note on 3C:
If the object was listed in the 3rd Cambridge Radio Catalog (Bennett 1961; 3C), then the full 3C designation is here. If not, then this field is blank.
Note on pos-ref:
The positions listed for the object come either from radio-interferometery measurements (usually) or from the original surveys (occasionally). This two-letter code indicates the source of the coordinates and corresponds to those listed in the Appendix.
Note on cl:
If the object has been optically identified, this gives the class of the object as a three character code as described in the following. If it has not, this field is blank.
Note on mag and rshift:
From Veron and Veron (1979) and Kuehr (1980).
Note on ind:
The two point spectral index . . . as determined between 2700 MHz and 5000 MHz. The spectral index is defined here as alpha., where the flux density is assumed proportional to frequency.
Note on type: For sources with flux density measurements at more than three frequencies, an attempt was made to fit a simple analytic function to the spectrum. This field contains one of four values depending on the result of this fit: LIN = The spectrum was successfully fitted by a straight line of the form y = A + Bx, where x = log v and y = log S Coefficients A and B only will contain data, coefficients C and D will be blank. EXP = The spectrum was fitted by a function of the type y = A + Bx + Cexp(Dx). All four coefficient fields will contain data. CPX = Although there were sufficient data points for the source (i.e., more than three) the spectrum could not be satisfactorily fitted with either of the above functional forms. Such a spectrum was designated complex because it would not be physically meaningful to devise some general analytic form to fit any spectral measurements (i.e. of variable sources whose spectra are generally complex). All coefficient fields will be blank. N<4 = There were data for no more than three frequencies and consequently no fit was attempted. All coefficient fields will be blank.
Byte-by-byte description of file: catalog.dat
--------------------------------------------------------------------------------
Bytes      Format    Units     Label         Explanation
--------------------------------------------------------------------------------
  1-  8    A8         ---      id            Source name
 10- 14    I5         Hz       freq-1        Frequency
 15        A1         ---      col-1         [:]
 16- 23    F8.2       Jy       flux-1       *Flux density
 24- 31    F8.2       Jy       e_flux-1     *Flux density error
 33- 35    I3         ---      ref-1        *Reference number
 36        A1         ---      ref-1-s      *Ref. number suffix
 41- 45    I5         Hz       freq-2        ?Frequency
 46        A1         ---      col-2         [:]
 47- 54    F8.2       Jy       flux-2       *?Flux density
 55- 62    F8.2       Jy       e_flux-2     *?Flux density error
 64- 66    I3         ---      ref-2        *?Reference number
 67        A1         ---      ref-2-s      *Ref. number suffix
 72- 76    I5         Hz       freq-3        ?Frequency
 77        A1         ---      col-3         [:]
 79- 85    F7.2       Jy       flux-3        ?Flux density
 86- 93    F8.2       Jy       e_flux-3      ?Flux density error
 95- 97    I3         ---      ref-3        *?Reference number
 98        A1         ---      ref-3-s      *Ref. number suffix
103-107    I5         Hz       freq-4        ?Frequency
108        A1         ---      col-4         [:]
109-116    F8.2       Jy       flux-4        ?Flux density
117-124    F8.2       Jy       e_flux-4      ?Flux density error
126-128    I3         ---      ref-4        *?Reference number
129        A1         ---      ref-4-s      *Ref. number suffix
----------------------------------------------------------------------------
Note on flux-*:
The flux density measurements are listed, in rows, in order of ascending frequency, so that consecutive frequencies run from left to right. The data may be read in ascending frequency order by using a repeating FORTRAN format statement to read successive records. All flux densities given . . . are on the scale of Baars et al. (1977). This scale is based on the absolute radio spectrum of Cassiopeia A. Between 0.3 and 30 GHz it is given by a flux density S+ = 2723 Jy and a spectral index &alpha. = -0.770 (epoch 1980.0) (Baars et al., 1977). See Kuehr et al. (1981) for a discussion of the details of the selection and compilation of flux densities. See also refs.dat
Note on e_flux-*:
Flux density errors were either taken directly from the catalogue or were calculated according to the formulae given there.
Note on ref-*:
This is the code number for the radio source catalog from which the particular flux density measurement came. refs.dat contains the radio source catalogs used and their attributes, sorted by code number. In one case the original catalog listed no source catalog and this field is blank.
Note on ref-*-s:
One source catalog code number (number 94) has three distinct catalogs associated with it, which are differentiated by , A, or B in this field. In all other cases this field is blank.
Byte-by-byte description of file: refs.dat
----------------------------------------------------------------------
Byte(s)  Format  Units    Label       Explanation
----------------------------------------------------------------------
 1-  3   I3       ---     code       *?Code number
 4       A1       ---     suf        *Suffix
 5- 11   F7.1     Hz      freq        ?Frequency
12- 17   F6.3     ---     fact       *?Conversion fact
18- 22   F5.1     Jy      flux        ?Flux density limit
24- 27   A4       ---     name-1     *Name 1
29- 32   A4       ---     name-2     *Name 2
34-124   A91      ---     ref        *Reference(s)
--------------------------------------------------------------------
Note on code:
The code numbers appearing in the flux density data records. The file is sorted on this datum. In four cases this field is blank, but the suffix contains an asterisk. This indicates a source catalog not directly referenced in any flux density measurement, but which the authors included in the Radio Source Catalogues list of the original paper. They are included here for completeness and are the first four source catalogs listed in this file. Code numbers 901-910 correspond to unpublished flux densities. If both this and the suffix fields are blank, the reference(s) field will be a continuation from the previous record.
Note on suf:
One code number (number 94) has three distinct source catalogs associated with it, which are differentiated by , A, or B in this field. An asterisk in this field indicates that the source catalog cited was not directly referenced in any flux density measurement, but was listed in the original paper as a source catalog. In all other cases this field is blank.
Note on fact:
This field gives the factor used to convert the flux densities in the catalog to the scale used (Baars et al. 1977) It is a ratio of the Baars et al. (1977) flux density scale to that of the source catalog at the frequency specified.
Note on Flux density limit
Before the data from a given source catalog were included in this compilation the values were checked against data on individual sources from all other catalogs to determine reliability. If there was a cut-off for inclusion from a specific catalog, that value is listed here.
Note on name-*:
If the catalog has a common designation (3C, PKs, etc.), it is listed here.
Note on ref:
The original paper or papers in which the catalog appeared. There are a maximum of three references for a single catalog.
History:
The Catalog of Extragalactic Radio Sources Having Flux Densities Greater Than 1 Jy at 5 GHz (EGRS) was sent to the Astronomical Data Center (ADC), NASA Goddard Space Flight Center, by the Centre de Donnees Stellaires (CDS), and received February 10, 1986.
The original tape contained a single text file formatted in the same manner as the published catalog; that is, with two header records per object and with the flux density measurements arranged in ascending order in columnar format. The two header records per object were combined into a single record. A FORTRAN program was written to rearrange the flux density measurements from columns into rows, so that the data may now be read in order of ascending flux by using a simple repeating FORTRAN format statement.
A FORTRAN program was run that checked the validity of each field according to its data type and value. ADC personnel created a separate file for the radio source catalogs. The data for this file were taken from Kuehr et al. (1981).
This work was supervised by Wayne W. Warren who also wrote the original document. To permit every line in the catalog to be read with the same format, the undersigned removed the header lines into a separate file (header.dat) and entered the source id in the first field of each record in catalog.dat. She also translated the document from Script to ASCII and rearranged it into the current standard form and altered the format tables appropriately.

References:

Baars, J. W. M., Genzel, R., Pauliny-Toth, I. I. K., and Witzel, A. 1977, Astron. Astrophys., 61, 99.
Bennett, A. S. 1961, Mem. R. A. S., 68, 163.
Kuehr, H. 1977, Astron. Astrophys. Suppl. Ser., 29, 139.
Kuehr, H. 1980, Ph.D. dissertation, Bonn.
Kuehr, H., Witzel, A., Pauliny-Toth, I. I. K., and Nauber, U. 1981, Astron. Astrophys. Suppl. Ser., 45, 367-430.
Veron, M. P. and Veron, P. 1979, Astron. Astrophys. Suppl. Ser., 36, 331.
Appendix:
For each position given in the header records of the catalog file there is also given a two letter code indicating the reference for this position. Codes from AA through BL . . . denote positions measured with a radio interometer, whereas codes SA through SP denote positions from the original survey instrument.
The following table defines the codes and the corresponding references. the original survey instrument.
Nancy G. Roman [ADC/SSDOO] July-22-1995