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Start Over Subject survey source Facility RADIO CATALOG
141. VLA XMM Large Scale Structure Field 325-MHz Source Catalog
ID:
ivo://nasa.heasarc/vlaxl325mh
Title:
VLA XMM Large Scale Structure Field 325-MHz Source Catalog
Short Name:
VLAXL325MH
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The XMM Large Scale Structure survey (XMM-LSS) is an X-ray survey aimed at studying the large scale structure of the Universe. The XMM-LSS field (centered at RA (J2000) = 02<sup>h</sup> 24<sup>m</sup> 00.27<sup>s</sup>, Dec (J2000) = -04<sup>o</sup> 09' 47.6") is currently being followed up using observations across a wide range of wavelengths, and in their paper the authors present the observational results of a low frequency radio survey of the XMM-LSS field using the Very Large Array at 74 and 325 MHz. This survey will map out the locations of the extragalactic radio sources relative to the large scale structure as traced by the X-ray emission. This is of particular interest because radio galaxies and radio-loud AGN show strong and complex interactions with their small and larger scale environment, and different classes of radio galaxies are suggested to lie at different places with respect to the large scale structure. For the phase calibration of the radio data, the authors used standard self-calibration at 325 MHz and field-base calibration at 74 MHz. Polyhedron-based imaging as well as mosaicking methods were used at both frequencies. At 74 MHz, the resolution was 30 arcseconds, the median 5-sigma sensitivity was ~ 162 mJy/beam and 666 sources were detected over an area of 132 square degrees. At 325 MHz, the resolution was 6.7 arcseconds, the median 5-sigma sensitivity was 4 mJy/beam, and 847 sources were detected over an area of 15.3 square degrees. At 325 MHz, a region of diffuse radio emission which is a cluster halo or relic candidate was detected. The observations were conducted using the VLA in July 2003 in the A-configuration (most extended) and in June 2002 in the B-configuration. This table contains the VLA 325-MHz source list, comprising 605 single sources and 615 components of 237 multiple sources, for a total of 1220 entries. (Notice that, in Section 4.1 of the reference paper, somewhat different numbers are given, i.e., the authors quote 621 single sources and 226 multiple sources). For the multiple sources, each component (A, B, etc.) is listed separately, in order of decreasing brightness. This table was created by the HEASARC in March 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/456/791">CDS Catalog J/A+A/456/791</a> file tablea1.dat. This is a service provided by NASA HEASARC .
142. Westerbork in the Southern Hemisphere (WISH) Source Catalog
ID:
ivo://nasa.heasarc/wish
Title:
Westerbork in the Southern Hemisphere (WISH) Source Catalog
Short Name:
WISH
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
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 (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/65">CDS Cat. VIII/65</a>) 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 <a href="http://cdsarc.u-strasbg.fr/ftp/cats/VIII/69A/uss.dat.gz">http://cdsarc.u-strasbg.fr/ftp/cats/VIII/69A/uss.dat.gz</a>). 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 <a href="http://www.astron.nl/wow/testcode.php?survey=1">http://www.astron.nl/wow/testcode.php?survey=1</a>. This table was created by the HEASARC in November 2010 base on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/69A">CDS catalog VIII/69A</a> file wish11.dat. This is a service provided by NASA HEASARC .
143. Westerbork Northern Sky Survey
ID:
ivo://nasa.heasarc/wenss
Title:
Westerbork Northern Sky Survey
Short Name:
WENSS
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Westerbork Northern Sky Survey (WENSS) is a low-frequency radio survey that covers the whole sky north of declination +30 degrees at a wavelength of 92 cm to a limiting flux density of approximately 18 milliJanskies (mJy) at the 5 sigma level. WENSS is a collaboration between the Netherlands Foundation for Research in Astronomy (NFRA/ASTRON) and the Leiden Observatory. The major personnel involved in WENSS include Ger de Bruyn, George Miley, Roeland Rengelink, Yuan Tang, Malcolm Bremer, Huub Rottgering, Ernst Raimond, Martin Bremer, and David Fullagar. The version of the WENSS Catalog as implemented at the HEASARC is a union of two separate catalogs obtained from the WENSS Website: the WENSS Polar Catalog (18186 sources above +72 degrees declination) and the WENSS Main Catalog (211234 sources in the declination region from +28 to +76 degrees). This database table was created by the HEASARC in February 2001 based on the tables wenssn10.cat (WENSS Main Catalog) and wenssp10.cat (WENSS Polar Catalog) obtained from the WENSS web site at <a href="http://www.strw.leidenuniv.nl/">http://www.strw.leidenuniv.nl/</a>. This is a service provided by NASA HEASARC .
144. WSRT Galactic Plane Compact 327-MHz Source Catalog
ID:
ivo://nasa.heasarc/wsrtgp
Title:
WSRT Galactic Plane Compact 327-MHz Source Catalog
Short Name:
WSRTGP
Date:
07 Mar 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Westerbork Synthesis Radio Telescope (WSRT) in the Netherlands has been used to survey the section of the galactic plane from +42 to +92 degrees Galactic Longitude l at a radio frequency of 327 MHz. Twenty-three overlapping synthesis fields were observed in the Galactic Latitude b band of |b| < 1.6 degrees. Each field was observed at two epochs, several years apart, to identify variable sources. Intensity data from the separate epochs were combined, and the resulting images mosaicked to produce a single image of the entire survey region. The sensitivity of the mosaic is typically a few mJy, corresponding to a detection level as low as 10 mJy/beam. The spatial resolution is 1' by 1' * cosec(Dec). The survey image provided the first high resolution view of the Galaxy at low radio frequencies, and included sections of the Sagittarius and Cygnus arms. These sections contain numerous extended features, among them supernova remnants, H II regions, "bubbles" of thermal emission, and large patches of amorphous galactic thermal emission. The inter-arm region is characterized by lower densities of extended features, but numerous discrete compact radio sources, most of which are background objects such as quasars and other types of active galactic nuclei. However, the resolution, sensitivity and low frequency of this survey make it ideal for detecting weak, non-thermal compact galactic sources, e.g. compact, low surface brightness SNRs and radio stars. Inspection of the survey image has produced a catalog of nearly 4000 discrete sources with sizes of less than about 3'. Gaussian model parameters for each compact source in the mosaicked images were obtained using the AIPS routine IMFIT. The background-removed intensity distribution of each source was fitted by a 2-dimensional Gaussian, parametrized by the source position, peak intensity, major and minor axes, and the position angle of the major axis. The catalog contains all sources having peak intensity > 5 times the rms noise level measured in the surrounding area of the image, and lists RA, Dec, flux density, and, if the source is resolved, the deconvolved major and minor axis and the position angle of the source. Sources were identified based on visual inspection of the images. In practice, a source had to have dimensions of less than a few arcminutes to be classified as a compact source. Most (85%) of the sources are either unresolved or only slightly resolved (major axis < 60"), but some sources have dimensions as large as 6'. A source was considered resolved if the area of its Gaussian model was greater than the area of the beam by more than 4 times its uncertainty. Approximately 15% of the sources are resolved, with dimensions of 1'- 3'. The spatial distribution of resolved sources shows concentrations toward the spiral arms and follows the warping of the Galactic disk over the length of the survey region, indicating that a sizable fraction is Galactic. In the reference paper, spectral indices are calculated for 1313 sources detected in other radio surveys at frequencies greater than 408 MHz. The resolved sources exhibit a bimodal spectral index distribution, with distinct non-thermal and thermal populations. Comparison with the IRAS Point Source Catalogue results in 118 identifications between WSRT and IRAS sources, which are listed in Table 1 of the reference paper. Most of these are thermal radio sources associated with compact Galactic objects such as H II regions and planetary nebulae. A search for variability among 2148 of the compact sources has resulted in 29 candidate low-frequency variable sources, which are listed in Table 2 of the reference paper. See the project website at <a href="http://www.ras.ucalgary.ca/wsrt_survey.html">http://www.ras.ucalgary.ca/wsrt_survey.html</a> for the WSRTGP images available in JPEG, PostScript, and FITS formats. This table was created by the HEASARC in February 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/107/239">CDS Catalog J/ApJS/107/239</a> file wsrt.dat. This is a service provided by NASA HEASARC .

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