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Phoenix Deep Survey 1.4-GHz Catalog
The initial Phoenix Deep Survey (PDS) observations with the Australia Telescope Compact Array (ATCA) have been supplemented by additional 1.4 GHz observations over the past few years. Here we present details of the construction of a new mosaic image covering an area of 4.56 deg<sup>2</sup> referred to as the Phoenix Deep field (PDF), an investigation of the reliability of the source measurements, and the 1.4 GHz source counts for the compiled radio catalog. The mosaic achieves a 1-sigma rms noise of 12 µJy at its most sensitive, and a homogeneous radio-selected catalog of over 2000 sources reaching flux densities as faint as 60 µJy has been compiled. The source parameter measurements are found to be consistent with the expected uncertainties from the image noise levels and the Gaussian source fitting procedure. A radio-selected sample avoids the complications of obscuration associated with optically selected samples, and by utilizing complementary PDS observations, including multicolor optical, near-infrared, and spectroscopic data, this radio catalog will be used in a detailed investigation of the evolution in star formation spanning the redshift range 0 < z < 1. The homogeneity of the catalog ensures a consistent picture of galaxy evolution can be developed over the full cosmologically significant redshift range of interest. The PDF covers a high-latitude region that is of low optical obscuration and devoid of bright radio sources. ATCA 1.4 GHz observations were made in 1994, 1997, 1999, 2000, and 2001 in the 6A, 6B, and 6C array configurations, accumulating a total of 523 hr of observing time. The initial 1994 ATCA observations (Hopkins et al. 1998, MNRAS, 296, 839; Hopkins 1998, PhD thesis) consisted of 30 pointings on a hexagonal tessellation, resulting in a 2 degrees diameter field centered on R.A. = 01<sup>h</sup> 14<sup>m</sup> 12.16<sup>s</sup>, Dec = -45<sup>o</sup> 44' 8.0" (J2000.0), with roughly uniform sensitivity of about 60 µJy rms. This survey was supplemented from 1997 to 2001 by extensive observations of a further 19 pointings situated on a more finely spaced hexagonal grid, centered on R.A. = 01<sup>h</sup> 11<sup>m</sup> 13.0<sup>s</sup>, Dec = -45<sup>o</sup> 45' 00" (J2000.0). The locations of all pointing centers are given in Table 1 of the reference paper. The final mosaic constructed from all 49 pointings was trimmed to remove the highest noise regions at the edges by masking out regions with an rms noise level greater than 0.25 mJy. The trimmed PDF mosaic image covers an area of 4.56 deg<sup>2</sup> and reaches to a measured level of 12 µJy rms noise in the most sensitive regions. The table contained here is the final merged catalog of PDS surveys based on the union of the 10% false discovery rate (FDR) threshold catalog (PDS_atca_fdr10_full_vis.cat) for the trimmed mosaic, visually edited to remove objects clearly associated with artifacts close to bright sources, containing 2058 sources, and the 10% FDR threshold catalog (PDS_atca_fdr10_deep.cat) for the 33' x 33' region centered on the most sensitive portion of the mosaic, containing 491 sources. The merged catalog was constructed to contain all unique catalogued sources; where common sources were identified, only the entry from PDS_atca_fdr10_deep.cat was retained. There are a total of 2148 sources in the final merged catalog, of which up to 10% may be false. This table was created by the HEASARC in November 2012 based on the file PDS_atca_fdr10_merge.cat, the merged PDS catalog (derived from the individual catalogs PDS_atca_fdr10_full_vis.cat and PDS_atca_fdr10_deep.cat as discussed in the Overview above), which was obtained from the first author's website <a href="https://web.archive.org/web/20171009234923/www.physics.usyd.edu.au/~ahopkins/phoenix/">https://web.archive.org/web/20171009234923/www.physics.usyd.edu.au/~ahopkins/phoenix/</a>. Some of the values for the name parameter in the HEASARC's implementation of this table were corrected in
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AT Large Area Survey (ATLAS) CDF-S/SWIRE 1.4-GHz Components Catalog
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This table contains some of the first results from the Australia Telescope Large Area Survey (ATLAS), which consists of deep 1.4-GHz radio observations of a 3.7 deg2 field surrounding the Chandra Deep Field-South (CDF-S), largely coincident with the infrared Spitzer Wide-Area Infrared Extragalactic (SWIRE) Survey. A total of 784 radio components are identified, corresponding to 726 distinct radio sources, nearly all of which are identified with SWIRE sources in the companion table ATLASCSID. Of the radio sources with measured redshifts, most lie in the redshift range 0.5 to 2 and include both star-forming galaxies and active galactic nuclei. The authors identify a rare population of infrared-faint radio sources that are bright at radio wavelengths but are not seen in the available optical, infrared, or X-ray data. Such rare classes of sources can only be discovered in wide, deep surveys such as this. The radio observations where made on 2002 Apr 4-27, Aug 24-29 and 2004 Jan 7-12, Feb 1-5, Jun 6-12 and Nov 24-30, with the Australia Telescope Compact Array (ATCA). The observations in 2002 were made in a mosaic of 7 overlapping fields, for a total of 149 hours of integration time, or 21.3 hours per pointing. The observations in 2004 were taken in the AT mosaic mode, in which the array was cycled around 21 pointing centers They total 173 hours of integration time, or 8.2 hours per pointing. All observations were made with two 128-MHz bands, centered on frequencies of 1344 and 1472 MHz. This table contains the list of 784 radio components given in Table 4 of the reference paper. The authors define a radio 'component' as a region of radio emission identified in the source extraction process. They define a radio 'source' as one or more radio components that appear to be physically connected and that probably correspond to one galaxy. Thus, the authors count a classical triple radio-loud source as being a radio source consisting of three radio components, but count a pair of interacting starburst galaxies as being two sources, each with one radio component. This table was created by the HEASARC in August 2012 based on CDS Catalog J/AJ/132/2409 file table4.dat. 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 .
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 .
Australia Telescope Hubble Deep Field-South 1.4-GHz Source Catalog
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This table derives from a paper which is part of a series describing the results from the Australia Telescope Hubble Deep Field-South (ATHDFS) survey obtained with the Australia Telescope Compact Array. This survey consists of observations at 1.4, 2.5, 5.2, and 8.7 GHz, all centered on the Hubble Deep Field-South. Herein are presented the first results from the extended observing campaign at 1.4 GHz. A total of 466 sources have been cataloged to a local sensitivity of 5-sigma (11 µJy rms). A source extraction technique is developed that (1) successfully excludes spurious sources from the final source catalogs and (2) accounts for the nonuniform noise in the image. A source catalog is presented, and the general properties of the 1.4-GHz image are discussed in the reference paper. In the latter, the authors also present source counts derived from their ATHDFS 1.4-GHz catalog. The 1.4 GHz observations were carried out by the Australia Telescope Compact Array over 4 years from 1998 to 2001. They consist of single pointings centered on RA (J2000.0) = 22h 33m 25.96s, Dec (J2000.0) = -60o 38' 09.0". This table was created by the HEASARC in November 2012 based on the CDS Catalog J/AJ/130/1371 file table1.dat. This is a service provided by NASA HEASARC .
ATLargeAreaSurvey(ATLAS)ELAIS-S1&CDF-S2.3-GHzSourceCatalog
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The Australia Telescope Large Area Survey (ATLAS) aims to image a 7 deg2 region centered on the European Large Area ISO Survey - South 1 (ELAIS-S1) field and the Chandra Deep Field South (CDF-S) at 1.4 GHz with high sensitivity (up to sigma ~ 10 uJy) to study the evolution of star-forming galaxies (SFGs) and Active Galactic Nuclei (AGN) over a wide range of cosmic time. The main goal of the present work is to study the radio spectra of an unprecedentedly large sample of sources (~ 2000 observed, ~ 600 detected in both frequencies). This table contains the results from ancillary radio observations at a frequency of 2.3 GHz which were obtained with the Australia Telescope Compact Array (ATCA). It comprises the catalog of sources with measured 1.4 GHz to 2.3 GHz spectral indices (Table 2 in the reference paper), compiled in the framework of ATLAS. It comprises only such sources which have unambiguous detections at both 1.4 GHz and 2.3 GHz, so no upper or lower limits on the spectral index based on non-detections are included. The 2.3-GHz detection limit is 300 uJy (equivalent to 4.5 sigma in the ELAIS-S1 field and 4.0 sigma in the CDF-S). The authors compute spectral indices between 1.4 GHz and 2.3 GHz using matched-resolution images and investigate various properties of their source sample in their dependence on their spectral indices. The authors find the entire source sample to have a median spectral index of -0.74, in good agreement with both the canonical value of -0.7 for optically thin synchrotron radiation and other spectral index studies conducted by various groups. Regarding the radio spectral index Alpha as indicator for source type, they find only marginal correlations so that flat or inverted spectrum sources are usually powered by AGN and hence conclude that, at least for the faint population, the spectral index is not a strong discriminator. They investigate the z-Alpha relation for their source sample and find no such correlation between spectral index and redshift at all. The authors do find a significant correlation between redshift and radio to near-infrared flux ratio, making this a much stronger tracer of high-z radio sources. They also find no evidence for a dependence of the radio-IR correlation on spectral index. This table was created by the HEASARC in August 2012 based on CDS Catalog J/A+A/544/A38 file spix_pub.dat. This is a service provided by NASA HEASARC .
VLA-COSMOS Project 1.4-GHz Joint Source Catalog
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In the context of the VLA-COSMOS Deep project, additional VLA A array observations at 1.4 GHz were obtained for the central degree of the COSMOS field and combined with the existing data from the VLA-COSMOS Large project. A newly constructed Deep mosaic with a resolution of 2.5 arcseconds was used to search for sources down to 4 sigma with 1 sigma ~ 12 µJy beam-1 in the central 50' x 50'. This new catalog is combined with the catalog from the Large project (obtained at 1.5" x 1.4" resolution) to construct a new Joint catalog. All sources listed in the new Joint catalog have peak flux densities of >= 5 sigma at 1.5" and/or 2.5" resolution to account for the fact that a significant fraction of sources at these low flux levels are expected to be slightly resolved at 1.5" resolution. All properties listed in the Joint catalog, such as peak flux density, integrated flux density, and source size, are determined in the 2.5" resolution Deep image. In addition, the Joint catalog contains 43 newly identified multi-component sources. This table was created by the HEASARC in June 2010 based on the electronic version of Table 3 from the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .
Allen Telescope Array Pi GHz Sky Survey (PiGSS) Deep Fields Source Catalog
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This table contains results from a total of 459 repeated 3.1-GHz radio continuum observations (of which 379 were used in a search for transient sources) of the ELAIS-N1, Coma, Lockman Hole, and NOAO Deep Wide Field Survey (NDWFS) fields as part of the Allen Telescope Array (ATA) Pi GHz Sky Survey (PiGSS). The observations were taken in 2 simultaneous 100-MHz wide bands centered at 3.04 and 3.14 GHz approximately once per day between 2009 May and 2011 April. Each image covers 11.8 square degrees and has 100" FWHM resolution. Deep images for each of the four fields have rms noise between 180 and 310 µJy (µJy), and the corresponding catalogs contain ~200 sources in each field. Typically 40-50 of these sources are detected in each single-epoch image. This represents one of the shortest cadence, largest area, multi-epoch surveys undertaken at these frequencies. The authors compared the catalogs generated from the combined images to those from individual epochs, and from monthly averages, as well as to legacy surveys. They undertook a search for transients, with particular emphasis on excluding false positive sources,but find no confirmed transients, defined here as sources that can be shown to have varied by at least a factor of 10. However, the authors found one source that brightened in a single-epoch image to at least six times the upper limit from the corresponding deep image. They also found a source associated with a z = 0.6 quasar which appears to have brightened by a factor ~3 in one of their deep images, when compared to catalogs from legacy surveys. The authors place new upper limits on the number of transients brighter than 10 mJy: fewer than 0.08 transients deg-2 with characteristic timescales of months to years; fewer than 0.02 deg-2 with timescales of months; and fewer than 0.009 deg-2 with timescales of days. In this study, the authors accepted only as real sources those that are independently detected in both frequencies in at least one epoch (with a position matching tolerance of 50", corresponding to a false match probability of <2%). Their threshold of ~ 4.2 sigma for detection in a single image corresponds to a threshold of ~ 5.9 sigma in the dual-image catalog. They generated catalogs for the deep fields, consisting only of sources detected at both frequencies, and these are contained in the present HEASARC table. Notice that the authors previously published a list of 425 radio sources in the NDWFS field in the constellation of Bootes in an earlier paper (Bower et al 2010, ApJ, 725, 1792, available as the HEASARC database table PIGSSBOOFD). In the 2013 paper, they have performed a partial re-analysis of these data to conform with the updated analysis techniques used on the other three fields. This table was created by the HEASARC in March 2013 based on electronic versions of Tables 2, 3, 4 and 5 (source lists for each of the 4 fields, ELAIS N1, Lockman, Coma, and NDWFS, respectively) from the reference paper which were obtained from the ApJ web site. The HEASARC has created a new parameter called field_name which identifies in which table/field the source can be found. Thus, to select only sources in the Lockman Hole field, the user should select field_name= 'Lockman'. This is a service provided by NASA HEASARC .
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 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 .
ATLargeAreaSurvey(ATLAS)CDF-S&ELAIS-S11.4-GHzDR2ComponentsCatalog
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This table derives from the first of two papers describing the second data release (DR2) of the Australia Telescope Large Area Survey (ATLAS) at 1.4 GHz. This survey comprises deep wide-field observations in total intensity, linear polarization, and circular polarization over the Chandra Deep Field-South (CDF-S) and European Large Area Infrared Space Observatory Survey (ELAIS)-South 1 regions. DR2 improves upon the first data release by maintaining consistent data reductions across the two regions, including polarization analysis, and including differential number counts in total intensity and linear polarization. Typical DR2 sensitivities across the mosaicked multi-pointing images are 30 µJy per beam at approximately 12 arcseconds by 6 arcseconds resolution over a combined area of 6.4 square degrees. In their paper, the authors present detailed descriptions of their data reduction and analysis procedures, including corrections for instrumental effects such as positional variations in image sensitivity, bandwidth smearing with a non-circular beam, and polarization leakage, and application of the BLOBCAT source extractor. They present the DR2 images and catalogs of components (discrete regions of radio emission) and sources (groups of physically associated radio components), and describe new analytic methods to account for resolution bias and Eddington bias when constructing differential number counts of radio components. The authors use the term 'component' to refer to an isolated region of emission that is best described by a single 2D elliptical Gaussian. Blended regions of contiguous emission may consist of multiple individual components. Following the terminology from Hales et al. (2012, MNRAS, 425, 979), a 'blob' is an agglomerated island of pixels above an SNR cutoff, which may encapsulate a single component or a blended region of emission. In Section 6 of the reference paper, the authors use the term 'source' to refer to single or multiple components belonging to the same astronomical object. This HEASARC table contains the ATLAS 1.4 GHz DR2 component catalog, a portion of which is displayed in Table A1 of the reference paper for guidance regarding its form and content. The catalog lists a total of 2,588 components in total intensity and linear polarization; no components were discovered in circular polarization. A list of the ATLAS 1.4 GHz DR2 sources, a portion of which is displayed in Table B1 of the reference paper for guidance regarding its form and content, is not included in this HEASARC table. This table was created by the HEASARC in October 2014 based on an electronic version of Table A1 from the reference paper which was obtained from the MNRAS web site. This is a service provided by NASA HEASARC .
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