- ID:
- ivo://nasa.heasarc/vlaxl74mhz
- Title:
- VLA XMM Large Scale Structure Field 74-MHz Source Catalog
- Short Name:
- VLAXL74MHZ
- Date:
- 02 May 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 74-MHz source list, comprising 617 single sources and 108 components of 51 multiple sources, for a total of 725 entries. (Notice that, in Section 4.3 of the reference paper, somewhat different numbers are given, i.e., the authors quote 615 single 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 tablea2.dat. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/vlaxl325mh
- Title:
- VLA XMM Large Scale Structure Field 325-MHz Source Catalog
- Short Name:
- VLAXL325MH
- Date:
- 02 May 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 .
- ID:
- ivo://nasa.heasarc/wish
- Title:
- Westerbork in the Southern Hemisphere (WISH) Source Catalog
- Short Name:
- WISH
- Date:
- 02 May 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 .
- ID:
- ivo://nasa.heasarc/wenss
- Title:
- Westerbork Northern Sky Survey
- Short Name:
- WENSS
- Date:
- 02 May 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 .
- ID:
- ivo://nasa.heasarc/wmapptsrc
- Title:
- WMAP Nine-Year Five-Band Point Source Catalog
- Short Name:
- WMAPPTSRC
- Date:
- 02 May 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Wilkinson Microwave Anisotropy Probe (WMAP) is designed to produce all-sky maps of the cosmic microwave background (CMB) anisotropy. The WMAP 9-Year Point Source Catalog contained herein has information on point sources in five frequency bands from 23 to 94 GHz, based on data from the entire 9 years of the WMAP sky survey from 10 Aug 2001 0:00 UT to 10 Aug 2010 0:00 UT, inclusive. The 5-band search technique used in the first-year, 3-year, 5-year and 7-year analyses now finds 501 point sources, compared to 471 point sources found in the 7-year analysis and 390 sources found in the 5-year analysis. The 5-band search method is largely unchanged from the 7-year analysis (Gold et al. 2011, ApJS, 192, 15). This method searches for point sources in each of the five WMAP wavelength bands. The nine-year signal-to-noise ratio map in each band is filtered in harmonic space by b<sub>l</sub>/[(b<sub>l</sub>)<sup>2</sup> C<sub>l</sub>(cmb) + C<sub>l</sub>(noise)], where b<sub>l</sub> is the transfer function of the WMAP beam response, C<sub>l</sub>(cmb) is the CMB angular power spectrum, and C<sub>l</sub>(noise) is the noise power. The filtering suppresses CMB and Galactic foreground fluctuations relative to point sources. For each peak in the filtered maps that is > 5 sigma in any band, the unfiltered temperature map in each band is fit with the sum of a planar base level and a beam template formed by convolving an azimuthally symmetrized beam profile with a skymap pixel. (This method was previously used by Weiland et al. (2011, ApJS, 192, 19) for selected celestial calibration sources and is more accurate than the Gaussian fitting that was used for the seven-year and earlier point source analyses). The peak temperature from each beam template fit is converted to a source flux density using the conversion factor Gamma given in Table 3 of the reference paper. The flux density uncertainty is calculated from the 1-sigma uncertainty in the peak temperature, and does not include any additional uncertainty due to Eddington bias. Flux density values are entered into the catalog for bands where they exceed 2 sigma and where the source width from an initial Gaussian fit is within a factor of two of the beam width. A point source catalog mask is used to exclude sources in the Galactic plane and Magellanic cloud regions. This mask has changed from the seven-year analysis in accordance with changes in the KQ85 temperature analysis mask. A map pixel is outside of the nine-year point source catalog mask if it is either outside of the diffuse component of the nine-year KQ85 temperature analysis mask or outside of the seven-year point source catalog mask. The present mask admits 83% of the sky, compared to 82% and 78% for the previous 7-year and 5-year versions, respectively. The authors identify possible 5-GHz counterparts to the WMAP sources found by cross-correlating with the GB6 (Gregory et al. 1996, ApJS, 103, 427), PMN (Griffith et al. 1994, ApJS, 90, 179; Griffith et al. 1995, ApJS, 97, 347; Wright et al. 1994, ApJS, 94, 111; Wright et al. 1996, ApJS, 103, 145), Kuehr et al. (1981, A&AS, 45, 367), and Healey et al. (2009, AJ, 138, 1032) catalogs. A 5-GHz source is identified as a counterpart if it lies within 11 arcminutes of the WMAP source position (the mean WMAP source position uncertainty is 4 arcminutes). When two or more 5 GHz sources are within 11 arcminutes, the brightest is assumed to be the counterpart and a multiple identification flag is entered in the catalog. A separate 9-year CMB-free Point Source Catalog (available in Browse as the <a href="/W3Browse/wmap/wmapcmbfps.html">WMAPCMBFPS</a> table) has information on point sources in three frequency bands from 41 to 94 GHz: the CMB-free method identified 502 point sources in a linear combination map formed from 41, 61 and 94 GHz band maps using weights such that CMB fluctuations are removed and flat-spectrum point sources are retained. The two catalogs have 387 sources in common. As noted by Gold et al. (2011, ApJS, 192, 15), differences in the source populations detected by the two search methods are largely caused by Eddington bias in the five-band source detections due to CMB fluctuations and noise. At low flux levels, the five-band method tends to detect point sources located on positive CMB fluctuations and to overestimate their fluxes, and it tends to miss sources located in negative CMB fluctuations. Other point source detection methods have been applied to WMAP data and have identified sources not found by our methods (e.g., Scodeller et al. (2012, ApJ, 753, 27); Lanz (2012, ADASS 7); Ramos et al. (2011, A&A, 528, A75), and references therein). For more details of how the point source catalogs were constructed, see Section 5.2.2 of the reference paper. This table was last updated by the HEASARC in January 2012 based on an electronic version of Table 18 from the 2012 (ApJS, submitted) paper which was obtained from the LAMBDA web site, the file <a href="http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_9yr_v5.txt">http://lambda.gsfc.nasa.gov/data/map/dr5/dfp/ptsrc/wmap_ptsrc_catalog_9yr_v5.txt</a>. The source_flag values were modified from those given in this file to reflect the values that were given in the printed version of the table. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/wsrtgp
- Title:
- WSRT Galactic Plane Compact 327-MHz Source Catalog
- Short Name:
- WSRTGP
- Date:
- 02 May 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 .
