- ID:
- ivo://nasa.heasarc/vlasxdfoid
- Title:
- VLA Subaru/XMM-Newton Deep Field 1.4-GHz Sources Optical/Near-IR Counterparts
- Short Name:
- VLASXDFOID
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- In Simpson et al. (2006, MNRAS, 372, 741, hereafter Paper I, available at the HEASARC as the <a href="/W3Browse/radio-catalog/vlasxdf1p4.html">VLASXDF1P4</a> table, the authors presented a catalog of 505 sources with 1.4-GHz peak radio flux densities greater than 100 uJy over a 0.81 deg<sup>2</sup> region of the Subaru/XMM-Newton Deep Field (SXDF) and some of the properties of their optical counterparts. In this study (Simpson et al. 2012, MNRAS, 421, 3060, Paper III in the series) the authors present spectroscopic and 11-band photometric redshifts for galaxies in the 100-uJy Subaru/XMM-Newton Deep Field radio source sample. The authors find good agreement between their redshift distribution and that predicted by the Square Kilometre Array (SKA) Simulated Skies project. They find no correlation between K-band magnitude and radio flux, but show that sources with 1.4-GHz flux densities below ~ 1 mJy are fainter in the near-infrared than brighter radio sources at the same redshift, and they discuss in their paper the implications of this result for spectroscopically incomplete samples where the K-z relation has been used to estimate redshifts. The authors use the infrared-radio correlation to separate their sample into radio-loud and radio-quiet objects and show that only radio-loud hosts have spectral energy distributions consistent with predominantly old stellar populations, although the fraction of objects displaying such properties is a decreasing function of radio luminosity. Many of the spectra presented in this study were obtained as part of the European Southern Observatory (ESO) program P074.A-0333, undertaken using the Visible Multi-Object Spectrograph (VIMOS) instrument on UT3/Melipal. Several observational campaigns have obtained spectra of objects within the SXDF, and Paper II in this series (Vardoulaki et al. 2008, MNRAS, 387, 505) presented spectra for 28 of the brightest 37 radio sources, obtained from a variety of sources. The near-infrared data used here come from the third data release (DR3) of the UKIRT (United Kingdom Infrared telescope) Infrared Deep Sky Survey, while the optical data in the UDS come from the SXDF, which comprises five separate Suprime-Cam pointings. This table was created by the HEASARC in August 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/421/3060">CDS Catalog J/MNRAS/421/3060</a> file table1.dat. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/vlasdf90cm
- Title:
- VLA SWIRE Deep Field 90-cm Source Catalog
- Short Name:
- VLASDF90CM
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results from the deepest radio continuum surveys to date at a radio wavelength of >~ 1m. The observations were taken with the VLA at 324.5 MHz covering a region of the SWIRE Spitzer Legacy survey, centered at RA and Dec of 10:46:00, +59:01:00 (J2000). The data reduction and analysis are described in the reference paper and a catalog of the sources detected above 5 sigma is presented herein. The authors also discuss the observed angular size distribution for the sample in their paper, and, using their deeper 20-cm survey of the same field (Owen and Morrison 2008, AJ, 136, 1889), they calculate spectral indices for sources detected in both surveys. They report log N-log S counts at 90 cm which show a flattening below 5 mJy. Given the median redshift of the population, z ~ 1, the spectral flattening and the flattening of the log N-log S counts occur at radio luminosities normally associated with AGN rather than with galaxies dominated by star formation. Observations were made of a single pointing center position (given above), with the VLA in A and C configurations for a total of almost 85 hours on-source between 2006 February and 2007 January. However, due to the ongoing EVLA upgrade, only 22 working antennae were typically avaliable in A and 18 in C. Thus, the total integration time was equivalent to ~ 63 hours in A and even less in C, with correspondingly less u-v coverage. This table was created by the HEASARC in September 2010 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/137/4846/">CDS catalog J/AJ/137/4846/</a> file table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vlasdf20cm
- Title:
- VLA SWIRE Deep Field 20-cm Source Catalog
- Short Name:
- VLASDF20CM
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results from deep radio observations taken with the Very Large Array at a center frequency of 1400 MHz covering a region of the Spitzer Wide-area InfraRed Extragalactic (SWIRE) Survey of the Spitzer Legacy survey, centered at RA and Dec of 10:46:00, +59:01:00 (J2000). The reduction and cataloging of radio sources are described in the reference paper. This table comprises the catalog of the sources detected above 5 sigma. The survey presented is the deepest so far in terms of the radio source density on the sky. Perhaps surprisingly, the sources down to the bottom of the catalog appear to have median angular sizes which are still greater than 1 arcsecond, like their cousins 10-100 times stronger. The shape of the differential log N-log S counts also seems to require a correction for the finite sizes of the sources in order to be self-consistent. If the log N-log S normalization remains constant at the lowest flux densities, there are about six sources per square arcminute at 15 µJy (µJy) at 20 cm. Given the finite-source size this implies that we may reach the natural confusion limit near 1 uJy. The observations were made with the VLA in A, B, C, and D configurations for a total of almost 140 hr on-source between 2001 December and 2004 January. Since the total time is dominated by the A congiguration, the final image for analysis has a resolution of ~1.6 arcseconds. This table was created by the HEASARC in September 2010 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/136/1889/">CDS catalog J/AJ/136/1889/</a> file table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vvds20cm
- Title:
- VLA-VIRMOS Deep Field 20-cm Source Catalog
- Short Name:
- VVDS20CM
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors of this table conducted a deep survey (rms noise ~ 17 microJansky or uJy) with the Very Large Array (VLA) at 1.4 GHz, with a resolution of 6 arcseconds, of a 1 deg<sup>2</sup> region included in the VIRMOS VLT Deep Survey that is centered at RA and Dec (J2000.0) of 02 26 00, -04 30 00, hereafter the VLA-VIRMOS Deep Field, or VLA-VDF. In the same field, they already had multiband photometry down to I<sub>AB</sub> = 25, and spectroscopic observations were to be obtained during the VIRMOS VLT survey. The homogeneous sensitivity over the whole field allowed them to derive a complete sample of 1054 radio sources (5-sigma limit) down to a limit of 0.08 mJy. In their paper, the authors give a detailed description of the data reduction and of the analysis of the radio observations, with particular care to the effects of clean bias and bandwidth smearing, and of the methods used to obtain the catalog of radio sources. To estimate the effect of the resolution bias on their observations, they have modeled the effective angular-size distribution of the sources in their sample and they have used this distribution to simulate a sample of radio sources. Finally, they present the radio count distribution down to 0.08 mJy derived from the catalog. Their counts are in good agreement with the best fit derived from earlier surveys, and are about 50% higher than the counts in the Hubble Deep Field (HDF). The radio count distribution clearly shows, with extremely good statistics, the change in the slope for the sub-mJy radio sources. 19 of the 1054 radio sources were fitted with multiple components. In such cases, the authors list in the catalog an entry for each of the components, identified with a trailing letter (A, B, C or D) in the source name, and an entry for the whole source, identified with a trailing T in the source name. In these cases the total flux was calculated using the task TVSTAT, which allows the integration of the map values over irregular areas, and the sizes are the largest angular sizes. Thus, this catalog contains 1103 entries on 1054 sources, including 49 entries on individual components of composite sources. This table was created by the HEASARC in February 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/403/857">CDS Catalog J/A+A/403/857</a> file catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vlaxl74mhz
- Title:
- VLA XMM Large Scale Structure Field 74-MHz Source Catalog
- Short Name:
- VLAXL74MHZ
- 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 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 .
- 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 .
- 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 .
- 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 .
- 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 .
