VIII/20 Catalog of 5 GHz Galactic Plane Sources (Haynes+ 1979)
A Catalogue of 5 GHz Galactic Plane Sources
Haynes R.F., Caswell J.L., and Simons L.W.J.
<Aust. J. Phys. Astrophys. Suppl 48, 1 (1979)>
=1979AuJPA..48....1H 1979AuJPA..48....1H
ADC_Keywords: Galactic plane ; Radio sources
Description:
This is a catalog of 915 sources in the galactic plane between
l=190 - 360 - 40 for -2 < b < 2. The l, b pair of galactic
coordinates is given in columns 1 and 2 and essentially constitutes
the galactic source name. The 1950 equatorial coordinates for each
source are given in columns 3 and 4, and values for the peak
brightness temperature and flux density are given in columns 5 and 6.
The reader should refer to Section 3 of the source reference for
information relating to the determination of the flux densities.
Column 7 gives an estimate of the source extension in minutes of arc.
Extents are given for source in nonconfused regions only. Finally, in
column 8 comments on each source are included where appropriate.
Identifications with known supernova remnants are included from the
compilation of Clark and Caswell (1976MNRAS.174..267C 1976MNRAS.174..267C).
Identifications with HII regions are based principally on H109alpha
recombination-line emission data, which are mostly obtained from
Wilson et al. (1970A&A.....6..364W 1970A&A.....6..364W) but with some unpublished Parkes
observations included also.
Source search techniques:
The detection of sources from the survey maps was made using an
automatic search routine with the CSIRO Cyber 76 computing system.
Maps were held using the NOD-2 format (see Haslam 1974,1975) in
machine readable form. Each map was systematically searched for
sources above the background level equivalent to a main beam
brightness temperature of 0.4 K. The initial search for sources
consisted of identifying those grid points in the map which exceed the
mean of the four adjacent surrounding points by a nominal 0.1 K (grid
point are at the Nyquist sample interval). Subsequently, the 'rough'
position and flux density were refined by a source-fitting technique.
The fitting procedure involved using a 16-point beam, function, where
the appropriate weighting for each grid point permitted the program to
interpolate to the best position for the peak of the source while
taking into account nearby galactic features. The beam-fitting
procedure was used either side (alternating between right ascension
and declination) of the nominal position to obtain the best estimate
of the position of each source. The resulting positions have an
accuracy comparable to the overall positional accuracy of the survey
(30" arc). Peak main beam brightness temperatures (determined by
fitting the 16-point beam response function at the deduced nominal
position) are also accurate to within the survey accuracy. Sources
with a peak beam brightness temperature of at least 0.2 K above the
background are included, except in confused regions; a point source of
0.2 K corresponds to 0.26 Jy.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 72 915 915 radio sources in the galactic plane
(positional accuracy ∼ 30")
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.3 deg GLON Galactic longitude
10- 16 F7.3 deg GLAT Galactic latitude
19- 20 I2 h RAh Right Ascension 1950 (hours)
22- 23 I2 min RAm Right Ascension 1950 (minutes)
25- 28 F4.1 s RAs Right Ascension 1950 (seconds)
31 A1 --- DE- Declination 1950 (sign)
32- 33 I2 deg DEd Declination 1950 (degrees)
35- 36 I2 arcmin DEm Declination 1950 (minutes)
38- 41 F4.1 arcsec DEs Declination 1950 (seconds)
44- 48 F5.2 K Tb Peak brightness temperature
51- 55 F5.2 Jy S *? Flux density at 5GHz
58- 59 I2 arcmin dim1 ? Extent (first dimension) or dim1
60 A1 --- --- [x ] 'x' for dim1 x dim2
61- 62 I2 arcmin dim2 ? Extent (second dimension) or dim2
66- 72 A7 --- Com *Identification Comment
--------------------------------------------------------------------------------
Note on S:
The source flux densities given in table1 were determined by
estimating the mean of the beam brightness temperatures at the four
points spaced at one-half of the half-power beamwidth from each
nominal source position. The quoted flux density is double the
difference between this mean and the peak observed source brightness
(with appropriate scaling, that is x1.3, from beam temperature to
janskys). In the calculation, the assumption was made that the source
is a point source. This technique results in a good estimate for point
sources even where there are several nearby sources or a confused
background. However, many of the sources are clearly extended. We have
not attempt to estimate integrated flux densities for these objects;
thus the catalogued flux densities are correct only for those
apparently 'point-like' radio sources. We strongly urge that the
catalogue be used only in close conjunction with the maps; they alone
can provide an adequate description of complex regions. The angular
size, when quoted in the table, refers to the full width of the source
measured in the galactic longitude and latitude directions. It is
intended only as a rough indication for sources much broader than the
beam size; in very confused regions no attempt was made to assess the
sizes of component sources.
Note on Com:
Identifications with known supernova remnants (SNR) from the
compilation of Clark and Caswell (1976MNRAS.174..267C 1976MNRAS.174..267C);
identifications with HII regions mostly from Wilson et al.
(1970A&A.....6..364W 1970A&A.....6..364W).
Abbreviations: C = Compact; E = Extended; PA = Part.
Acknowledgements:
The original CDS documentation by M.J. Wagner, F. Ochsenbein (1993)
was included in this ReadMe file.
References:
Clark, D.H., and Caswell, J.L. (1976). Mon. Not. Astron. Soc. 174, 267.
(1976MNRAS.174..267C 1976MNRAS.174..267C)
Haslam, C.G.T. (1974). Astron. Astrophys. 15, 333.
Haslam, C.G.T. (1975). Proc. Astron. Soc. Aust. 2, 331.
Haynes, R.F., Caswell, J.L., and Simons, L.W. (1978).
Aust. J. Phys. Astrophys. Suppl. No 45, 1.
(1978AuJPA..45....1H 1978AuJPA..45....1H)
Wilson, T.L., Mezger, P.G., Gardner, F.F., and Milne, D.K. (1970).
Astron. Astrophys. 6, 364. (1970A&A.....6..364W 1970A&A.....6..364W)
(End) M.J.Wagner, F. Ochsenbein [CDS]; C.-H. Lyu [Hughes STX/NASA] 08-Apr-1996