- ID:
- ivo://nasa.heasarc/vlaonccat
- Title:
- VLA Orion Nebula Cluster Compact Source Catalog
- Short Name:
- VLAONCCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a deep centimeter-wavelength catalog of the Orion Nebula Cluster (ONC), based on a 30-hr single-pointing observation with the Karl G. Jansky Very Large Array (JVLA) in its high-resolution A configuration using two 1-GHz bands centered on 4.7 and 7.3 GHz. A total of 556 compact sources were detected in a map with a nominal rms noise of 3 µJy/beam, limited by complex source structure and the primary beam response. Compared to previous catalogs, these detections increase the sample of known compact radio sources in the ONC by more than a factor of seven. The new data show complex emission on a wide range of spatial scales. Following a preliminary correction for the wideband primary-beam response, the authors determine radio spectral indices for 170 sources whose index uncertainties are less than +/-0.5. They compare the radio to the X-ray and near-infrared point-source populations, noting similarities and differences. The observations were carried out with the JVLA of the National Radio Astronomy Observatory on 2012 September 30 and October 2-5 under the auspices of the project code SD630. Data were taken using the VLA's C-band (4-8 GHz) receivers in full polarization mode, with two 1-GHz basebands centered at 4.736 and 7.336 GHz to provide a good baseline for source spectral index determination. Apart from the first epoch, the field was simultaneously observed with the Chandra X-Ray Observatory. Mostly of interest for variability information, these data will be presented as part of a follow-up paper. This table was created by the HEASARC in September 2016 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/822/93">CDS Catalog J/ApJ/822/93</a> file table1.dat (the compact source catalog). Some of the values for the name parameter in the HEASARC's implementation of this table were corrected in April 2018. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/vlass821p4
- Title:
- VLA SDSS Stripe 82 Survey 1.4-GHz Source Catalog
- Short Name:
- VLASS821P4
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from a high-resolution radio survey of the Sloan Digital Sky Survey (SDSS) Southern Equatorial Stripe, also known as Stripe 82. This 1.4-GHz survey was conducted with the Very Large Array (VLA) primarily in the A configuration, with supplemental B configuration data to increase sensitivity to extended structure. The survey has an angular resolution of 1.8 arcseconds and achieves a median rms noise of 52 µJy/beam (µJy/beam) over 92 deg<sup>2</sup>. This is the deepest 1.4-GHz survey to achieve this large of an area, filling a gap in the phase space between small, deep and large, shallow surveys. It also serves as a pilot project for a larger high-resolution survey with the Expanded Very Large Array (EVLA). The authors discuss the technical design of the survey and details of the observations, and outline their method for data reduction, in the reference paper. They present a catalog of 17,969 isolated radio components, for an overall source density of ~195 sources deg<sup>-2</sup>. The astrometric accuracy of the data is excellent, with an internal check utilizing multiply observed sources yielding an rms scatter of 0.19 arcseconds in both Right Ascension and Declination. A comparison to the SDSS DR7 Quasar Catalog further confirms that the astrometry is well-tied to the optical reference frame, with mean offsets of 0.02" +/- 0.01" in Right Ascension, and 0.01" +/- 0.02" in Declination. A check of their photometry reveals a small, negative CLEAN-like bias on the level of 35 uJy. The authors report on the catalog completeness, finding that 97% of FIRST-detected quasars are recovered in the new Stripe 82 radio catalog, while faint, extended sources are more likely to be resolved out by the resolution bias. In their paper, they conclude with a discussion of the optical counterparts to the catalog sources, including 76 newly detected radio quasars. The full catalog as well as a search page and cutout server are available online at <a href="http://third.ucllnl.org/cgi-bin/stripe82cutout">http://third.ucllnl.org/cgi-bin/stripe82cutout</a>. The SDSS Stripe 82 observations were made with the National Radio Astronomy Observatory's (NRAO's) VLA. The data were collected over two VLA cycles, 2007-2008 and 2008-2009. The majority of the observations were taken in the A configuration, but the authors also obtained B-configuration coverage of the area in order to improve the sampling of the Fourier (U-V) plane and to increase sensitivity to the extended structure. Area 1 (delineated in black in Figure 1(a) of the paper) was covered in the A and B configurations in 2007-2008, and Area 2 (delineated in purple in Figure 1(a) of the paper) in the A and B configurations in 2008-2009. Area 1 is made up of 275 pointings, and Area 2 has 374, coming to 649 fields, and 92 deg<sup>2</sup> covered in total. This table was created by the HEASARC in August 2013 based on a complete machine-readable version of Table 1 from the reference paper which was kindly provided by the first author. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/vlasxdf1p4
- Title:
- VLA Subaru/XMM-Newton Deep Field 1.4-GHz Source Catalog
- Short Name:
- VLASXDF1P4
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from the deep radio imaging at 1.4 GHz of the 1.3-deg<sup>2</sup> Subaru/XMM-Newton Deep Field (SXDF), made with the Very Large Array (VLA) in B and C configurations. This resulted in a radio map of the entire field, and a catalog of 505 sources covering 0.8 deg<sup>2</sup> to a peak flux density limit of 100 microJansky (µJy), which corresponds to signal-to-noise (S/N) ratios of between 5 and 8. Robust optical identifications are provided for 90 per cent of the sources, and suggested identifications are presented for all but 14 (of which seven are optically blank, and seven are close to bright contaminating objects). The authors show that the optical properties of the radio sources do not change with flux density, suggesting that active galactic nuclei (AGN) continue to contribute significantly at faint flux densities. they test this assertion by cross-correlating their radio catalog with the X-ray source catalog and conclude that radio-quiet AGN become a significant population at flux densities below 300 uJy, and may dominate the population responsible for the flattening of the radio source counts if a significant fraction of them are Compton-thick. The SXDF was observed with NRAO's VLA in B-array using the 14 overlapping pointings arranged an an hexagonal pattern that are listed in Table 1 of the reference paper. Three test observations of pointings 1, 4 and 6 were taken on 2001 May 17, and the rest of the data were obtained in 13 runs, each lasting 4.5 hours, between 2002 August 10 and September 9. All 14 pointings were re-observed in C-array on 2003 January 15 to provide additional information on larger angular scales. This table contains the catalog of 505 detected radio sources and their proposed optical counterparts (the latter taken mostly from the ultra-deep BRíz' Suprime-Cam images of the SXDF). As mentioned above, 14 of these 505 radio sources have no suggested identifications. Additionally, 7 of the radio sources (source numbers 16, 114, 129, 263, 360, 361 and 488) have 2 listed optical identifications: in such cases, there are 2 entries for each source listed detailing the alternative optical counterparts, and with identical sets of radio parameters. Thus, there are 512 = 505 + 7 entries in this table. This table was created by the HEASARC in August 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/372/741">CDS Catalog J/MNRAS/372/741</a> file table3.dat. This is a service provided by NASA HEASARC .
- 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 .
- ID:
- ivo://nasa.heasarc/vlacdfscat
- Title:
- VLA Survey of Chandra Deep Field South
- Short Name:
- VLACDFSCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results from 20 and 6 cm VLA deep observations of the Chandra Deep Field-South (CDF-S), including the Extended CDF-S (E-CDF-S). In the reference paper, the authors discuss the radio properties of 266 cataloged radio sources, of which 198 are above a 20-cm completeness level reaching down to 43 microJanskies (µJy) at the center of the field. Survey observations made at 6 cm over a more limited region cover the original CDF-S to a comparable level of sensitivity as the 20-cm observations. Of 266 cataloged radio sources, 52 have X-ray counterparts in the CDF-S and a further 37 have counterparts in the E-CDF-S area not covered by the 1 Ms exposure. Using a wide range of material, the authors have found optical or infrared counterparts for 254 radio sources, of which 186 have either spectroscopic or photometric redshifts. Three radio sources have no apparent counterpart at any other wavelength. Measurements of the 20-cm radio flux density at the position of each CDF-S X-ray source detected a further 30 radio sources (not included in this table) above a conservative 3-sigma detection limit. X-ray and sub-millimeter observations have been traditionally used as a measure of AGN and star formation activity, respectively. These new observations probe the faint end of both the star formation and radio galaxy/AGN population, as well as the connection between the formation and evolution of stars and SMBHs. Both of the corresponding gravitational and nuclear fusion-driven energy sources can lead to radio synchrotron emission. AGN and radio galaxies dominate at high flux densities. Although emission from star formation becomes more prominent at the microJansky levels reached by deep radio surveys, even for the weakest sources, an apparent significant contribution from low-luminosity AGN as well as from star formation is still found. Notice that are 319 entries in this table corresponding to the 266 catalogued radio sources, due to the fact that some of these sources have multiple components. In such cases, the composite source as well as each of its components are listed as separate entries, e.g., source 7 which has 3 components (A, B and C) has 4 entries in this table. This table was created by the HEASARC in November 2008 based on the electronic version of Table 1 from the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/skyview/stripe82vla
- Title:
- VLA Survey of SDSS Stripe 82
- Short Name:
- Stripe82VLA
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This survey is a deep, high resolution radio survey of a relatively small region that has particularly deep coverage in the Sloan Digital Sky Survey. As described in the reference abstract: This is a high-resolution radio survey of the Sloan Digital Sky Survey (SDSS) Southern Equatorial Stripe, a.k.a., Stripe 82. This 1.4 GHz survey was conducted from 2007 to 2009 with the Very Large Array primarily in the A-configuration, with supplemental B-configuration data to increase sensitivity to extended structure. The survey has an angular resolution of 1.8" and achieves a median rms noise of 53 microJy/beam over 92 square degrees. This is the deepest 1.4 GHz survey to achieve this large of an area filling in the phase space between small&deep and large&shallow surveys. <p> The astrometric accuracy of the data is excellent with errors in observed sources of 0.10" in both RA and declination. A comparison with the SDSS DR7 Quasar Catalog confirms that the astrometry is well tied to the optical reference frame with mean offsets of 0.02+/-0.01" in RA and 0.01+/-0.02 in declination. Provenance: TBD. This is a service of NASA HEASARC.
- 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 .
