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17081. VLA SDSS Stripe 82 Survey 1.4-GHz Source Catalog
ID:
ivo://nasa.heasarc/vlass821p4
Title:
VLA SDSS Stripe 82 Survey 1.4-GHz Source Catalog
Short Name:
VLASS821P4
Date:
28 Feb 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 .
17082. VLA search for 5GHz radio transients
ID:
ivo://CDS.VizieR/J/ApJ/740/65
Title:
VLA search for 5GHz radio transients
Short Name:
J/ApJ/740/65
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a 5GHz survey with the Very Large Array (VLA) and the expanded VLA, designed to search for short-lived (<~1day) transients and to characterize the variability of radio sources at milli-Jansky levels. A total sky area of 2.66deg^2^, spread over 141 fields at low Galactic latitudes (b~6-8{deg}), was observed 16 times with a cadence that was chosen to sample timescales of days, months, and years. Most of the data were reduced, analyzed, and searched for transients in near real-time. Interesting candidates were followed up using visible light telescopes (typical delays of 1-2hr) and the X-ray Telescope on board the Swift satellite. The final processing of the data revealed a single possible transient with a peak flux density of f_{nu}_~2.4mJy. Furthermore, we use the data to measure the source variability on timescales of days to years, and we present the variability structure function of 5GHz sources.
17083. VLASS QL Ep.1 Catalog, CIRADA version
ID:
ivo://CDS.VizieR/J/ApJS/255/30
Title:
VLASS QL Ep.1 Catalog, CIRADA version
Short Name:
J/ApJS/255/30
Date:
09 Feb 2022 14:56:38
Publisher:
CDS
Description:
The Very Large Array Sky Survey (VLASS) is observing the entire sky north of -40{deg} in the S-band (2-4GHz), with the highest angular resolution (2.5") of any all-sky radio continuum survey to date. VLASS will cover its entire footprint over three distinct epochs, the first of which has now been observed in full. Based on Quick Look images from this first epoch, we have created a catalog of 1.9x10^6 reliably detected radio components. Due to the limitations of the Quick Look images, component flux densities are underestimated by ~15% at S>3mJy/beam and are often unreliable for fainter components. We use this catalog to perform statistical analyses of the 3GHz radio sky. Comparisons with the Faint Images of the Radio Sky at Twenty cm survey (FIRST) show the typical 1.4-3GHz spectral index to be -0.71. The radio color-color distribution of point and extended components is explored by matching with FIRST and the LOFAR Two Meter Sky Survey. We present the VLASS source counts, dN/dS, which are found to be consistent with previous observations at 1.4 and 3GHz. Resolution improvements over FIRST result in excess power in the VLASS two-point correlation function at angular scales <7", and in 18% of active galactic nuclei associated with a single FIRST component being split into multi-component sources by VLASS.
17084. VLA Subaru/XMM-Newton Deep Field 1.4-GHz Source Catalog
ID:
ivo://nasa.heasarc/vlasxdf1p4
Title:
VLA Subaru/XMM-Newton Deep Field 1.4-GHz Source Catalog
Short Name:
VLASXDF1P4
Date:
28 Feb 2025
Publisher:
NASA/GSFC HEASARC
Description:
This table contains results from the deep radio imaging at 1.4 GHz of the 1.3-deg&lt;sup&gt;2&lt;/sup&gt; 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&lt;sup&gt;2&lt;/sup&gt; to a peak flux density limit of 100 microJansky (&micro;Jy), 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&#39;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 BR&iacute;z&#39; 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 &lt;a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/372/741"&gt;CDS Catalog J/MNRAS/372/741&lt;/a&gt; file table3.dat. This is a service provided by NASA HEASARC .
17085. VLA Subaru/XMM-Newton Deep Field 1.4-GHz Sources Optical/Near-IR Counterparts
ID:
ivo://nasa.heasarc/vlasxdfoid
Title:
VLA Subaru/XMM-Newton Deep Field 1.4-GHz Sources Optical/Near-IR Counterparts
Short Name:
VLASXDFOID
Date:
28 Feb 2025
Publisher:
NASA/GSFC HEASARC
Description:
In Simpson et al. (2006, MNRAS, 372, 741, hereafter Paper I, available at the HEASARC as the &lt;a href="/W3Browse/radio-catalog/vlasxdf1p4.html"&gt;VLASXDF1P4&lt;/a&gt; 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&lt;sup&gt;2&lt;/sup&gt; 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 &lt;a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/421/3060"&gt;CDS Catalog J/MNRAS/421/3060&lt;/a&gt; file table1.dat. This is a service provided by NASA HEASARC .
17086. VLA survey at 6 cm in the Lockman Hole
ID:
ivo://CDS.VizieR/J/A+A/398/901
Title:
VLA survey at 6 cm in the Lockman Hole
Short Name:
J/A+A/398/901
Date:
21 Oct 2021
Publisher:
CDS
Description:
A deep radio image was obtained with the Very Large Array at 6cm in the Lockman Hole, during three runs of eleven hours each on January 16, 17 and 19, 1999 at 4835 and 4885MHz with a bandwidth of 50MHz in C configuration. From these data a catalogue of 63 radio sources was extracted, having a maximum distance of 10arcmin from the field center and a peak flux density greater than 4.5 times the local rms noise. The noise level in the central part of the field is ~11{mu}Jy.
17087. VLA survey for faint compact radio sources in ONC
ID:
ivo://CDS.VizieR/J/ApJ/831/155
Title:
VLA survey for faint compact radio sources in ONC
Short Name:
J/ApJ/831/155
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Karl G. Jansky Very Large Array 1.3, 3.6, and 6cm continuum maps of compact radio sources in the Orion Nebular Cluster (ONC). We mosaicked 34arcmin^2^ at 1.3cm, 70arcmin^2^ at 3.6cm and 109arcmin^2^ at 6cm, containing 778 near-infrared detected young stellar objects and 190 Hubble Space Telescope-identified proplyds (with significant overlap between those characterizations). We detected radio emission from 175 compact radio sources in the ONC, including 26 sources that were detected for the first time at these wavelengths. For each detected source, we fitted a simple free-free and dust emission model to characterize the radio emission. We extrapolate the free-free emission spectrum model for each source to ALMA bands to illustrate how these measurements could be used to correctly measure protoplanetary disk dust masses from submillimeter flux measurements. Finally, we compare the fluxes measured in this survey with previously measured fluxes for our targets, as well as four separate epochs of 1.3cm data, to search for and quantify the variability of our sources.
17088. VLA survey of 0016+16, Abell 665, and Abell 2218
ID:
ivo://CDS.VizieR/J/AJ/98/1148
Title:
VLA survey of 0016+16, Abell 665, and Abell 2218
Short Name:
J/AJ/98/1148
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used the VLA to survey the fields of the three clusters of galaxies; 0016+16, Abell 665 (0826+66) and Abell 2218 (1635+66) at 1440 MHz, 4860 MHz, and 14940 MHz (for the brighter sources). The survey was aimed at finding radio sources which might contaminate the Sunyaev-Zel'dovich effect. We have detected 86 sources in these three clusters and examined Palomar sky survey prints for possible optical identifications.
17089. VLA survey of Abell clusters. II.
ID:
ivo://CDS.VizieR/J/ApJS/80/501
Title:
VLA survey of Abell clusters. II.
Short Name:
J/ApJS/80/501
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present radio contour maps, models, and optical identifications for 130 radio galaxies in Abell clusters of galaxies.
17090. VLA survey of Abell clusters. IV.
ID:
ivo://CDS.VizieR/J/AJ/109/853
Title:
VLA survey of Abell clusters. IV.
Short Name:
J/AJ/109/853
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is the fourth in a series of papers describing an in depth study of a large statistical sample of radio galaxies in Abell clusters. This sample forms the basis of a detailed optical and radio study of the host galaxy properties, environments, and evolutionary models for radio galaxies as a class of objects. In this paper, we examine the radio detection statistics as a function of cluster morphological type, galaxy richness, and spatial location within the cluster galaxy distribution. These relationships are also parametrized as a function of radio power. The spatial distributions of the radio sources as a function of distance from the cluster center indicate that radio galaxies are preferentially located at small radii from the center of the cluster potential. This is observed as a factor of 2-3 excess over that predicted by a King-model surface-density distribution. The excess is higher in the upper radio power bin. This result is easily explained, however, from the spatial distribution of the brightest galaxies and the relationship between radio and optical luminosity. The sample is divided into richness classes 0, 1, and 2, according to Abell's criterion, and in two radio power ranges. While simple counting shows that richer clusters have more radio galaxies in both radio power bins, when the detections are scaled to the number of galaxies surveyed in each cluster, no significant correlations are found. This result implies that the number of radio galaxies detected simply scales with the number of galaxies surveyed. The higher galaxy density (and presumably higher ICM gas density) in richer clusters does not appear to affect the rate of radio source formation. The clusters are divided into Rood-Sastry and Bautz-Morgan morphological types. While it would appear that the more regular clusters have higher radio detection rates, when the classes are normalized to the number of galaxies, the radio detection rates are found to be identical regardless of cluster morphology. In conclusion, it is the optical properties of the host galaxy which most influence both the radio detection rate and the radio source properties. The cluster properties, galaxy density, and spatial location of the galaxy do not significantly affect the observed radio statistics.

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