WISH - Westerbork in the Southern Hemisphere (WISH) Source Catalog

Overview

The Westerbork in the Southern Hemishpere (WISH) is a low-frequency (352 MHz) radio survey that covers most of the sky (the Galactic Plane region |b| < 10 degrees is excluded) between -26 and -9 degrees (1.60 sr) at a wavelength of 92 cm to a limiting flux density of approximately 18 mJy (5 sigma). WISH is the southern extension of the Westerbork Northern Sky Survey (WENSS). Due to the very low elevation of the observations, the survey has a much lower resolution in declination than in right ascension (54" x 54" cosec[delta]). A correlation with the 1.4GHz NVSS (CDS Cat. VIII/65) shows that the positional accuracy is less constrained in declination than in right ascension, but there is no significant systematic error. This table contains 90,357 352-MHz flux density measurements, some of them being multiple observations of the same sources, some of them measurements of individual components of multi-component sources. While the abstract of the reference paper states that there are 73,570 sources in this catalog, the HEASARC counts 77,414 unique sources in this version of the table.

The correlation with the NVSS was also used to construct a sample of faint Ultra Steep Spectrum sources (Table 2 in the reference paper, available at http://cdsarc.u-strasbg.fr/ftp/cats/VIII/69A/uss.dat.gz). This sample is aimed at increasing the number of known high redshift radio galaxies to allow detailed follow-up studies of these massive galaxies and their environments in the early Universe.

WISH is a collaboration between the Netherlands Foundation for Research in Astronomy (NFRA/ASTRON) and the Leiden Observatory. Carlos De Breuck, Yuan Tang, Ger de Bruyn, Huub Rottgering, Wil van Breugel, and Roeland Rengelink. For more information, see the WENSS home page at http://www.astron.nl/wow/testcode.php?survey=1.

Catalog Bibcode

2002A&A...394...59D

References

The Westerbork in the Southern Hemisphere (WISH) Survey
     De Breuck C., Tang Y., de Bruyn A.G., Rottgering H., van Breugel W.
    <Astron. Astrophys. 394, 59 (2002)>
    =2002A&A...394...59D

Provenance

This table was created by the HEASARC in November 2010 base on CDS catalog VIII/69A file wish11.dat.

Parameters

Name
The position-based source designation. This is close to the form recommended by the CDS Dictionary of Nomenclature of Celestial Objects, viz., 'WISH BHHMM.m-DDMMA', where the numerical part of the name is the truncated B1950.0 position of the radio source (to 0.1 minutes of time in RA and 1 arcminute in Dec) and the letter suffixes are used to identify individual components of multi-component sources. The CDS further suggested adding a further lower-case suffix 'a', 'b' or 'c' to the names of sources with multiple measurements, but the HEASARC has retained this as a separate parameter (obs_index) since it is an attribute of the observation rather than of the actual source.

Obs_Index
This parameter is set to 'a', 'b' or 'c' to identify sources which have multiple flux density measurements. The multiple entries provide variability information. Some double entries in the same field are however due to problems in the source-fitting algorithm, and are marked with a 'P' in the value of the source_flag parameter.

RA
The Right Ascension of the radio source in the selected equinox. This was taken from the J2000.0 source position in the original reference table which was specified to a precision of 0.01 seconds of time.

Dec
The Declination of the radio source in the selected equinox. This was taken from the J2000.0 source position in the original reference table which was specified to a precision of 0.1 arcseconds.

LII
The Galactic Longitude of the radio source.

BII
The Galactic Latitude of the radio source.

Source_Type
The radio source type, as follows:

      S = Single component source.
      M = Multicomponent source.
      C = Component of a multicomponent source.
      E = Extended source (more than four components).

Source_Flag
This flag parameter is set to 'P' (in the original catalog an asterisk was used) to indicate that there were problems in fitting the source. In the case of such problems, the source parameters were obtained using 'aperture' integration.

Flux_352_MHz
The peak flux density of the radio source at 352 MHz, in mJy/beam.

Int_Flux_352_MHz
The integrated flux density of the radio source at 352 MHz, in mJy.

Major_Axis
The fitted major axis of the radio source, in arcseconds. The mean ratio between the fitted major and minor axes of the WISH sources is 5.00, reflecting the high ellipticity of the synthesized beam.

Minor_Axis
The ftted minor axis of the radio source, in arcseconds.

Position_Angle
The fitted position angle of the radio source, in degrees.

Flux_352_MHz_Error
The local RMS-noise level in the vicinity of the source, in mJy/beam.

WISH_Frame
The WISH frame from which the source information was obtained. The positions of the mosaic centers and the flux density correction factors of the 49 frames comprising the WISH are listed in Table 1 of the reference paper.

Contact Person

Questions regarding the WISH database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:36:47 EDT