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Australia Telescope Low-Brightness Survey Source Catalog
The Australia Telescope Low-brightness Survey (ATLBS) regions have been mosaic imaged at a radio frequency of 1.4 GHz with 6 arcseconds angular resolution and 72 microJansky per beam (µJy/beam) rms noise. The images (centered at RA 00<sup>h</sup> 35<sup>m</sup> 00<sup>s</sup>, Dec -67<sup>o</sup> 00' 00" and RA 00<sup>h</sup> 59<sup>m</sup> 17<sup>s</sup>, Dec -67<sup>o</sup> 00' 00", J2000 epoch) cover 8.42 deg<sup>2</sup> sky area and have no artifacts or imaging errors above the image thermal noise. Multi-resolution radio and optical r-band images (made using the 4 m CTIO Blanco telescope) were used to recognize multi-component sources and prepare a source list of 1366 1.4-GHZ sources; the detection threshold was 0.38 mJy in a low-resolution radio image made with beam FWHM of 50 arcseconds. Radio source counts in the flux density range 0.4-8.7 mJy are estimated, with corrections applied for noise bias, effective area correction, and resolution bias. The resolution bias is mitigated using low-resolution radio images, while effects of source confusion are removed by using high-resolution images for identifying blended sources. Below 1 mJy the ATLBS counts are systematically lower than the previous estimates. Showing no evidence for an upturn down to 0.4 mJy, they do not require any changes in the radio source population down to the limit of the survey. The work suggests that automated image analysis for counts may be dependent on the ability of the imaging to reproduce connecting emission with low surface brightness and on the ability of the algorithm to recognize sources, which may require that source finding algorithms effectively work with multi-resolution and multi-wavelength data. The work underscores the importance of using source lists - as opposed to component lists - and correcting for the noise bias in order to precisely estimate counts close to the image noise and determine the upturn at sub-mJy flux density. This table was created by the HEASARC in April 2013 based on an electronic version of Table 2 from the reference paper that was obtained from the ApJ web site.. This is a service provided by NASA HEASARC .
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Australia Telescope Hubble Deep Field-South 2.5, 5.2 and 8.7-GHz Source Catalog
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Deep radio observations of a wide region centered on the Hubble Deep Field-South (HDF-S) have been performed, providing one of the most sensitive sets of radio observations acquired on the Australia Telescope Compact Array (ATCA) to date. A central rms of ~ 10 µJy is reached at four frequencies (1.4, 2.5, 5.2, and 8.7 GHz). In this table, the full source catalogs from the 2.5, 5.2, and 8.7 GHz observations are presented to complement the data for the 1.4 GHz observations which were presented in Paper II (Huynh et al., 2005, AJ, 130, 1373, available at the HEASARC as the ATHDFS1P4G table) in this series, along with a detailed analysis of image quality and noise. The authors also have produced a consolidated catalog of all of their ATCA observations of the HDF-S by matching sources across all four of the frequencies in their survey (available at the HEASARC as the ATHDFSCCAT table). The details of the observations and data reduction are discussed in detail in Paper I of this series (Norris et al., 2005, AJ, 130, 1358) and summarized in Table 1 of the reference paper. The observations consist of single pointings centered on RA (J2000.0) = 22h 33m 25.96s, Dec (J2000.0) = -60o 38' 09.0" (2.5 GHz), and RA (J2000.0) = 22h 32m 56.22s, Dec (J2000.0) = -60o 33' 02.7" (5.2 and 8.7 GHz). The 5.2 and 8.7 GHz observations are centered on the HST WFPC field, while the 2.5 GHz observations were pointed halfway between the WFPC field and a bright confusing source to allow the bright source to be well cleaned from the 2.5 GHz image. At 5 sigma, the 5.2 and 8.7 GHz catalogs have over 96% reliability. At 2.5 GHz, the authors have enough statistics to examine the 5 - 5.5 sigma sources, and find that these are only about 40% reliable. With a SNR greater than 5.5 sigma, the 2.5 GHz catalog would have about 99% reliability. The authors thus cut off the catalogs at 5.5, 5, and 5 sigma for 2.5, 5.2, and 8.7 GHz, respectively. The final catalogs have 71, 24, and 6 sources at 2.5, 5.2, and 8.7 GHz, respectively. Given a prior 1.4 GHz position, it may be feasible to push the detection limit lower than 5 sigma. The authors searched for low-SNR sources by matching 3 - 5 sigma sources that lie within 2 sigma positional uncertainty of a 1.4 GHz source. The positional uncertainty was determined by adding the average 1.4 GHz uncertainty (1.1") in quadrature with the positional uncertainty of a 3 sigma source. At 2.5 GHz the allowed positional offset is 3.8", and for 5.2 and 8.7 GHz it is 2.8". Thus, there are 71, 18, and 2 sources at 2.5, 5.2, and 8.7 GHz, respectively, which are low-SNR high-frequency counterparts to 1.4 GHz sources. The authors included these sources in supplementary catalogs. This HEASARC table contains all 101 primary sources detected at 2.5, 5.2, and 8.7 GHz, as well as the 91 supplementary sources described above (the latter are flagged by having source_flag values of 'S'), for a grand total of 192 radio sources. This table was created by the HEASARC in December 2012 based on the CDS Catalog J/AJ/130/1371 files table47.dat, table58.dat and table68.dat, which contain the entire contents of Tables 4, 5, 6, 7 and 8 from the published paper. This is a service provided by NASA HEASARC .
Australia Telescope Hubble Deep Field-South Combined Source Catalog
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Deep radio observations of a wide region centered on the Hubble Deep Field-South (HDF-S) have been performed, providing one of the most sensitive sets of radio observations acquired on the Australia Telescope Compact Array (ATCA) to date. A central rms of ~ 10 µJy is reached at four frequencies (1.4, 2.5, 5.2, and 8.7 GHz). In this table, the combined 4-frequency AT-HDFS Catalog including fluxes and spectral indices for sources detected at 1.4, 2.5, 5.2, and/or 8.7 GHz observations is presented to complement the single-frequency radio data for the 1.4 GHz observations which were presented in Paper II (Huynh et al., 2005, AJ, 130, 1373, available at the HEASARC as the ATHDFS1P4G table) in this series, and for the 2.5, 5.2, and/or 8.7 GHz observations which were presented in the reference paper (Paper III, Huynh et al., 2007, AJ, 133, 1331, available at the HEASARC as the ATHDFS3FRQ table). The details of the observations and data reduction are discussed in detail in Paper I of this series (Norris et al., 2005, AJ, 130, 1358) and summarized in Table 1 of the reference paper. The radio observations were carried out by the ATCA over 4 years from 1998 to 2001. The observations at 1.4 and 2.5 GHz consist of single pointings centered on RA (J2000.0) = 22h 33m 25.96s, Dec (J2000.0) = -60o 38' 09.0". The observations at 5.2 and 8.7 GHz consist of single pointings centered on RA (J2000.0) = 22h 32m 56.22s, Dec (J2000.0) = -60o 33' 02.7". The 5.2 and 8.7 GHz observations are centered on the HST WFPC field, while the 1.4 and 2.5 GHz observations were pointed halfway between the WFPC field and a bright confusing source to allow the bright source to be well cleaned from the 1.4 and 2.5 GHz images. This HEASARC table contains the final consolidated catalog of 473 individual sources and gives the flux densities at all frequencies for each individual radio source. It contains the 466 1.4-GHz sources from Paper II together with 5 unmatched 2.5-GHz sources and 2 unmatched 8.7-GHz sources. The procedure that the authors used to construct this catalog is discussed in Section 6 of the reference paper. This table was created by the HEASARC in December 2012 based on the CDS Catalog J/AJ/130/1371 file table9.dat which contains the entire contents of Table 9 from the published paper. This is a service provided by NASA HEASARC .
Phoenix Deep Survey Optical and Near-Infrared Counterparts Catalog
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Using a deep Australia Telescope Compact Array (ATCA) radio survey covering an area of ~3 deg2 to a 4-sigma sensitivity of >= 100 µJy (µJy) at 1.4 GHz, the authors study the nature of faint radio galaxies. The region, 2 degrees in diameter and centered on RA and Dec (J2000.0) of 1h 14m 12.16s, -45o 44' 08.0" (Galactic latitude of -71o), is known as the Phoenix Deep Field. About 50% of the detected radio sources are identified with an optical counterpart revealed by CCD photometry to mR = 22.5 magnitudes. Near-infrared (K-band) data are also available for a selected sample of the radio sources, while spectroscopic observations have been carried out for about 40% of the optically identified sample. These provide redshifts and information on the stellar content. Emission-line ratios imply that most of the emission-line sources are star-forming galaxies, with a small contribution (~ 10%) from Seyfert 1/Seyfert 2 type objects. The authors also find a significant number of absorption-line systems, likely to be ellipticals. These dominate at high flux densities ( > 1 mJy) but are also found at sub-mJy levels. Using the Balmer decrement, they find a visual extinction AV = 1.0 for the star-forming faint radio sources. This moderate reddening is consistent with the (V - R) and (R - K) colors of the optically identified sources. For emission-line galaxies, there is a correlation between the radio power and the H-alpha luminosity, in agreement with the result of Benn et al. (1993, MNRAS, 263, 98). This suggests that the radio emission of starburst radio galaxies is a good indicator of star formation activity. When calculating luminosities, the authors assume a cosmology with a Hubble constant H0 of 50 km s-1 Mpc-1 and a deceleration parameter q0 of 0.5. This table was created by the HEASARC in June 2013 based on an electronic version of Table 1 from the reference paper, which details the photometric (optical and near-infrared), radio, spectroscopic and intrinsic properties of the faint radio sources in the PDS with established redshifts, which was obtained from the CDS web site (their catalog J/MNRAS/306/708 file table1.dat). This is a service provided by NASA HEASARC .
ATLargeAreaSurvey(ATLAS)SpectroscopicClasses&RedshiftsCatalog
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The Australia Telescope Large Area Survey (ATLAS) has surveyed 7 square degrees of sky around the Chandra Deep Field South (CDF-S) and the European Large Area ISO Survey-South 1 (ELAIS-S1) fields at 1.4 GHz. ATLAS aims to reach a uniform sensitivity of 10 µJy (µJy) beam-1 rms over the entire region with first data release currently reaching ~ 30 uJy beam-1 rms. Here the authors present 466 new spectroscopic redshifts for radio sources in ATLAS as part of their optical follow-up program. Of the 466 radio sources with new spectroscopic redshifts, 142 have star-forming optical spectra, 282 show evidence for active galactic nuclei (AGN) in their optical spectra, 10 have stellar spectra and 32 have spectra revealing redshifts, but with insufficient features to classify. The authors compare their spectroscopic classifications with two mid-infrared diagnostics and find them to be in broad agreement. ATLAS is a pathfinder for the forthcoming Evolution Map of the Universe (EMU) survey and the data presented in this paper will be used to guide EMU's survey design and early science papers. This paper uses H0 = 70 km s-1 Mpc-1, OmegaM = 0.3 and OmegaLambda = 0.7, and the web-based calculator of Wright (2006, PASP, 118, 1711) to estimate the distance-dependent physical parameters. This table was created by the HEASARC in March 2013 based on an electronic version of Table 2 from the reference paper which was obtained from the MNRAS web site. 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 .
Australia Telescope Chandra Deep Field-South and SDSS Stripe 82 20-GHz Sources
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This table contains a source catalog, one of the first results from a deep, blind radio survey carried out at 20 GHz with the Australia Telescope Compact Array, with follow-up observations at 5.5, 9 and 18 GHz. The Australia Telescope 20GHz (AT20G) deep pilot survey covers a total area of 5 deg2 in the Chandra Deep Field South and in Stripe 82 of the Sloan Digital Sky Survey. The authors estimate the survey to be 90% complete above 2.5 mJy. Of the 85 sources detected, 55% have steep spectra (spectral index alpha1.420 < -0.5) and 45% have flat or inverted spectra (alpha1.420 >= -0.5). The steep-spectrum sources tend to have single power-law spectra between 1.4 and 18 GHz, while the spectral indices of the flat- or inverted-spectrum sources tend to steepen with frequency. Among the 18 inverted-spectrum (alpha1.420 >= 0.0) sources, 10 have clearly defined peaks in their spectra with alpha1.45.5 > 0.15 and alpha918 < -0.15. On a 3-yr time-scale, at least 10 sources varied by more than 15 percent at 20 GHz, showing that variability is still common at the low flux densities probed by the AT20G-Deep Pilot (AT20GDP) survey. The AT20G-Deep Pilot survey was carried out with he ATCA in 2009 July, shortly after the telescope was provided with a new wide-bandwidth correlator, the CABB. As a result of this upgrade to the telescope, the observing bandwidth was increased by a factor of 16, from 2x128 to 2x2048 MHz, in all bands (ranging from 1.1 to 105 GHz), greatly increasing the sensitivity of continuum observations. These observations were made in continuum mode using two 2048-MHz CABB bands centered at 19 and 21 GHz, with each 2048-MHz band divided into 2048 1-MHz channels. All four Stokes parameters were measured. This table was created by the HEASARC in August 2015 based on the union of CDS Catalog J/MNRAS/439/1212 files table2.dat (the 50 sources in the 3-hr field) and table3.dat (the 35 sources in the 21-hr field). This is a service provided by NASA HEASARC .
Australia Telescope 20-GHz Survey Bright Source Sample
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The Australia Telescope 20-GHz (AT20G) Survey is a blind survey of the whole southern sky at 20 GHz (with follow-up observations at 4.8 and 8.6 GHz) carried out with the Australia Telescope Compact Array from 2004 to 2007. The Bright Source Sample (BSS) is a complete flux-limited sub-sample of the AT20G Survey catalog comprising 320 extragalactic (|b| > 1.5 degrees) radio sources south of declination -15 degrees with 20-GHz flux densities S20GHz > 0.50 Jy (500 mJy). Of these sources, 218 have near simultaneous observations at 8 and 5 GHz. In the reference paper, the authors present an analysis of the radio spectral properties in total intensity and polarization, size, optical identifications and redshift distribution of the BSS sources. Optical identifications provided an estimation of redshift for 186 sources with median values of 1.20 and 0.13 for QSOs and galaxies, respectively. This table was created by the HEASARC in August 2008 based on the CDS Catalog J/MNRAS/384/775 files table2.dat and table3.dat. This is a service provided by NASA HEASARC .
Australia Telescope Hubble Deep Field-South Optical Identifications Catalog
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The Australia Telescope Hubble Deep Field-South (ATHDF-S) survey of the Hubble Deep Field-South (HDF-S) reaches sensitivities of ~ 10 µJy (µJy) at 1.4, 2.5, 5.2, and 8.7 GHz, making the ATHDF-S one of the deepest surveys ever performed with the Australia Telescope Compact Array (ATCA). This table contains the optical identifications of the ATHDF-S radio sources (the radio data from which are available in summarized form in the HEASARC ATHDFSCCAT table) using data from the literature. The authors find that ~ 66% of the radio sources have optical counterparts to an I magnitude of 23.5 mags. Deep Hubble Space Telescope (HST) imaging of the area identifies a further 12% of the radio sources. In this table, the authors present data from new spectroscopic observations for 98 of the radio sources and supplement these spectroscopic redshifts with photometric ones calculated from five-band optical imaging. The radio observations and data reduction are detailed in Papers I-III of this series: 
 I = Norris et al., 2005, AJ, 130, 1358; II = Huynh et al., 2005, AJ, 130, 1373, available at the HEASARC as the ATHDFS1P4G table; III = Huynh et al., 2007, AJ, 133, 1331, available at the HEASARC as the ATHDFSCCAT and ATHDFS3FRQ tables.
Palunas et al. (2000, ApJ, 541, 61) observed the HDF-S region using the Big Throughput Camera (BTC) on the Cerro Tololo Inter-American Observatory (CTIO) 4m during 1998 September. Images were taken in the Sloan Digital Sky Survey (SDSS) u, Johnson B and V, and Cousins R and I filters. In addition, the authors obtained spectra of the ATHDF-S radio sources over two service nights in 2001 July and 2003 October using the multi-fiber 2dF instrument of the Anglo-Australian Telescope (AAT). They acquired low-resolution (9 Angstrom) spectra over the wavelength range from 3800 to 8000 Angstroms. This table was created by the HEASARC in December 2012 based on the CDS Catalog J/AJ/135/2470 files table1.dat and table10.dat which contain the entire contents of Tables 1 and 10 from the published paper. This is a service provided by NASA HEASARC .
Australia Telescope 20-GHz (AT20G) High-Angular Resolution Catalog
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This table contains the high-angular-resolution catalog for the Australia Telescope 20-GHz (AT20G) survey, using the high-angular-resolution 6-km antenna data at the baselines of ~4500 m of the Australia Telescope Compact Array (ATCA). The authors have used the data to produce the visibility catalog that separates the compact active galactic nuclei (AGNs) from the extended radio sources at the 0.15-arcsecond angular scale, corresponding to the linear size scale of 1 kpc at redshifts higher than 0.7. They find the radio population at 20 GHz to be dominated by compact AGNs constituting 77% of the total sources in the AT20G. In the paper, they introduce the visibility-spectra diagnostic plot, produced using the AT20G cross-matches with lower frequency radio surveys at 1 GHz [the NRAO VLA Sky Survey (NVSS: Condon et al. 1998, AJ, 115, 1693) and the Sydney University Molonglo Sky Survey (SUMSS: Mauch et al. 2003, MNRAS, 342, 1117)], that separates the 20-GHz population into distinct sub-populations of the compact AGNs, the compact steep-spectrum (CSS) sources, the extended AGN-powered sources and extended flat-spectrum sources. The extended flat-spectrum sources include a local thermal emitting population of high-latitude planetary nebulae and also gravitational lens and binary black hole candidates among the AGNs. The authors find a smooth transition in properties between the CSS sources and the AGN populations. The visibility catalog, together with the main AT20G survey, provides an estimate of angular size scales for sources in the AT20G and an estimate of the flux arising from central cores of extended radio sources. The identification of the compact AGNs in the AT20G survey provides high-quality calibrators for high-frequency radio telescope arrays and very large baseline interferometry observations. This table was created by the HEASARC in December 2013 based on machine-readable versions of Tables 2 and 3 from the reference paper which were obtained from the MNRAS web site. This is a service provided by NASA HEASARC .
Giant Metrewave Radio Telescope 1h XMM/Chandra Survey Fld 610-MHz Source Catalog
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This table contains the results of a deep 610-MHz survey of the 1hr XMM-Newton/Chandra survey area with the Giant Metre-wave Radio Telescope (GMRT). The resulting maps have a resolution of ~7 arcseconds and an rms noise limit of 60 µJy (µJy). To a 5-sigma detection limit of 300 uJy, the authors detect 223 sources within a survey area of 64 arcminutes in diameter. They compute the 610-MHz source counts and compare them to those measured at other radio wavelengths. The well-known flattening of the Eucidean-normalized 1.4-GHz source counts below ~ 2 mJy, usually explained by a population of starburst galaxies undergoing luminosity evolution, is seen at 610 MHz. In 2004 August, the 1hr field (centered at (J2000.0) RA, Dec = 01h 45m 27s, -04o 34' 42") was observed for approximately 4.5 hours at 610 MHz with the GMRT. Observations were carried out in dual band, spectral line mode, the former to maximize bandwidth and the latter to minimize chromatic aberration. Two sidebands, each of 128 spectral channels of 125 kHz, were centred on 602 and 618 MHz to give a total of 32 MHz bandwidth, with two independent circular polarizations recorded. Sources were extracted with the AIPS task SAD. A conservative peak flux density detection limit of 5 sigma (i.e. 300 uJy) was used to minimize the number of noise spikes spuriously detected as sources. In the areas surrounding the five brightest sources, detection was performed separately with higher detection thresholds to account for the higher rms noise. Within the 20% power radius of the GMRT primary beam at 610 MHz (32 arcminutes), 213 sources were discovered above a 5-sigma peak flux density detection limit of 300 uJy. In order to determine the success of the SAD source extraction, both the science images and the residual noise maps were carefully inspected. There were eight extended sources where the Gaussian model fit by SAD inadequately described the data: these are marked by source_flag = 'a' in this table. The characteristics of these sources were determined using the AIPS task TVSTAT, and contour plots of them are shown in Fig. 1 of the reference paper. Five of these appear to contain two peaks joined by extended emission, that is, they are double-lobe sources. This table was created by the HEASARC in June 2012 based on CDS Catalog J/MNRAS/378/995 file table1.dat. This is a service provided by NASA HEASARC .
7C 151-MHz Low-Declination Survey Catalog
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The Cambridge Low Frequency Synthesis Telescope (CLFST) has been used at 151 MHz to survey a region of 1393 square degrees, in the range of RA from 9h to 16h, and of Dec from 20o to 35o, with an angular resolution of 108 x 108cosec(Dec) arcsec2. The rms noise in the maps is in general ~ 35 - 55 mJy/beam, but varies considerably and exceeds this in some areas. The authors have extracted sources with signal-to-noise ratio > 5.5, a total of 5526 sources, and this table contains the catalog of their positions and flux densities. This table was created by the HEASARC in October 2010 based on CDS table J/MNRAS/282/779 file 7c_low.dat. This is a service provided by NASA HEASARC .
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