- ID:
- ivo://nasa.heasarc/wsrt20anep
- Title:
- AKARI NEP WSRT 20-cm Source Catalog
- Short Name:
- WSRT20ANEP
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Westerbork Radio Synthesis Telescope (WSRT) has been used in 2004 to make a deep radio survey of an ~1.7 degree<sup>2</sup> field coinciding with the AKARI north ecliptic pole (NEP) deep field. The WSRT survey consisted of 10 pointings, mosaiced with enough overlap to maintain a similar sensitivity across the central region that reached as low as 21 microJanskies/beam (µJy/beam) at 1.4 GHz. The observations, data reduction and source count analysis are presented in the reference paper, along with a description of the overall scientific objectives. A catalog containing 462 sources detected with a resolution of 17.0 arcsecs by 15.5 arcsecs is presented. The differential source counts calculated from the WSRT data have been compared with those from the shallow VLA-NEP survey of Kollgaard et al. (1994, ApJS, 93, 145), and show a pronounced excess for sources fainter than ~1 mJy, consistent with the presence of a population of star-forming galaxies at sub-mJy flux levels. The AKARI NEP deep field is the focus of a major observing campaign conducted across the entire spectral region. The combination of these data sets, along with the deep nature of the radio observations will allow unique studies of a large range of topics including the redshift evolution of the luminosity function of radio sources, the clustering environment of radio galaxies, the nature of obscured radio-loud active galactic nuclei, and the radio/far-infrared correlation for distant galaxies. This catalog provides the basic data set for a future series of paper dealing with source identifications, morphologies, and the associated properties of the identified radio sources. This table was created by the HEASARC in March 2011 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/517/A54">CDS catalog J/A+A/517/A54</a> file table2.dat. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/pigssboofd
- Title:
- Allen Telescope Array Pi GHz Sky Survey (PiGSS) Boo Field Source Catalog
- Short Name:
- PIGSSBOOFD
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Pi GHz Sky Survey (PiGSS) is a key project of the Allen Telescope Array (ATA). PiGSS is a 3.1 GHz survey of radio continuum emission in the extragalactic sky with an emphasis on synoptic observations that measure the static and time-variable properties of the sky. During the 2.5 year campaign, PiGSS will twice observe ~250,000 radio sources in the 10,000 deg<sup>2</sup> region of the sky with b > 30 degrees to an rms sensitivity of ~1 mJy. Additionally, sub-regions of the sky will be observed multiple times to characterize variability on timescales of days to years. Presented here are the results from observations of a 10 deg<sup>2</sup> region in the Bootes constellation overlapping the NOAO Deep Wide Field Survey field. The PiGSS image was constructed from 75 daily observations distributed over a 4 month period and has an rms flux density between 200 and 250 microJy. This represents a deeper image by a factor of 4-8 than the authors will achieve over the entire 10,000 deg<sup>2</sup>. In this table, they provide flux densities, source sizes, and spectral indices for the 425 sources detected in the image. They identify ~100 new flat-spectrum radio sources, and project that, when completed, PiGSS will identify 104 flat-spectrum sources. In their paper the authors identify one source that is a possible transient radio source. This survey provides new limits on faint radio transients and variables with characteristic durations of months. This table was created by the HEASARC in March 2011 based on electronic versions of Tables 2 and 4 from the reference paper which were obtained from the ApJ web site. The HEASARC changed the sign of the values of the last parameter in Table 4 (herein called spectral_index_3_error) from negative to positive. In March 2013, after receiving a clarification from Steve Croft, the HEASARC corrected the names of the 4 parameters describing the source sizes (to reflect the fact that they were diameters nor radii) to major_axis, minor_axis, fit_major_axis and fit_minor_axis. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pigsselcnf
- Title:
- Allen Telescope Array Pi GHz Sky Survey (PiGSS) Deep Fields Source Catalog
- Short Name:
- PIGSSELCNF
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 microJy (uJy), 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<sup>-2</sup> with characteristic timescales of months to years; fewer than 0.02 deg<sup>-2</sup> with timescales of months; and fewer than 0.009 deg<sup>-2</sup> 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 .
- ID:
- ivo://nasa.heasarc/atats
- Title:
- Allen Telescope Array Twenty-cm Survey (ATATS) Source Catalog
- Short Name:
- ATATS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the source catalog from the Allen Telescope Array Twenty-centimeter Survey (ATATS), a multi-epoch (12 visits), 690 deg<sup>2</sup> radio image and catalog at 1.4 GHz. The survey is designed to detect rare, very bright transients as well as to verify the capabilities of the ATA to form large mosaics. The combined image using data from all 12 ATATS epochs has an rms noise sigma = 3.94 mJy beam<sup>-1</sup> and a dynamic range of 180, with a circular beam of 150 arcseconds FWHM. It contains 4408 sources to a limiting sensitivity of 5 sigma = 20 mJy beam<sup>-1</sup>. The authors compare the catalog generated from this 12-epoch combined image to the NRAO VLA Sky Survey (NVSS), a legacy survey at the same frequency, and find that they can measure source positions to better than ~ 20 arcseconds. For sources above the ATATS completeness limit, the median flux density is 97% of the median value for matched NVSS sources, indicative of an accurate overall flux calibration. The authors examine the effects of source confusion due to the effects of differing resolution between the ATATS and NVSS on their ability to compare flux densities. They detect no transients at flux densities greater than 40 mJy in comparison with NVSS and place a 2 sigma upper limit of 0.004 deg<sup>-2</sup> on the transient rate for such sources. These results suggest that the >~ 1 Jy transients reported by Matsumara et al. (2009, AJ, 138, 787) may not be true transients, but rather variable sources at their flux density threshold. This table was created by the HEASARC in September 2010 based on the electronic version of Table 2 from the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/aegis20id
- Title:
- All-Wavelength Extended Groth Strip Int. Survey (AEGIS) 20-cm Fully Id-ed Sample
- Short Name:
- AEGIS20ID
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Infrared 3.6 - 8.0 micron (µm) images of the Extended Groth Strip (EGS) yield plausible counterpart identifications for all but one of 510 radio sources in the AEGIS20 S(1.4 GHz) > 50 microJansky (µJy) sample (Ivison et al. 2007, ApJ, 660, L77, available at the HEASARC as the AEGIS20 database table). This is the first such deep sample that has been effectively 100% identified. Achieving the same identification rate at R band would require observations reaching R<sub>AB</sub> > 27. Spectroscopic redshifts are available for 46% of the sample and photometric redshifts for an additional 47%. Almost all of the sources with 3.6-um AB magnitudes brighter than 19 have spectroscopic redshifts z < 1.1, while fainter objects predominantly have photometric redshifts with 1 <~ z <~ 3. Unlike more powerful radio sources that are hosted by galaxies having large stellar masses within a relatively narrow range, the AEGIS20 counterparts have stellar masses spanning more than a factor of 10 at z ~ 1. The sources are roughly 10% - 15% starbursts at z <~ 0.5 and 20%-25% active galactic nuclei mostly at z > 1, with the remainder of uncertain nature. Throughout this study, magnitudes are in the AB system, and the notation [w] means the AB magnitude at wavelength w in um. Source distances are based on standard Lambda-CDM cosmology with H<sub>0</sub> = 71 km s<sup>-1</sup> Mpc<sup>-1</sup> and Omega<sub>M</sub> = 0.27. Practical calculation of luminosity distances was based on the program ANGSIX (Kayser et al. 1997, A&A, 318, 680). This table was created by the HEASARC in July 2013 based on the electronic versions of Tables 1, 3, 4, and 5 from the reference paper which were obtained from the ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/aegis20
- Title:
- All-Wavelength Extended Groth Strip Int. Survey (AEGIS) VLA 20-cm Source Catalog
- Short Name:
- AEGIS20
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from AEGIS20, a radio survey of the Extended Groth Strip (EGS) conducted with the Very Large Array (VLA) at a frequency of 1.4 GHz. The resulting catalog contains 1122 emitters (HEASARC Note: The abstract of the original reference paper said 1123, but as noted by Willner et al. (2012, ApJ, 756, 72: footnote 10, one entry ('EGS20 J142303.7+532224.5') was listed twice in the original catalog), and it is sensitive to ultraluminous (10<sup>12</sup> solar luminosities) starbursts to z <= 1.3, well matched to the redshift range of the DEEP2 spectroscopic survey in this region. The authors use stacking techniques to explore the microJansky-level emission from a variety of galaxy populations selected via conventional criteria - Lyman break galaxies (LBGs), distant red galaxies (DRGs), UV-selected galaxies, and extremely red objects (EROs) - determining their properties as a function of color, magnitude, and redshift and their extinction-free contributions to the history of star formation. This study confirms the familiar pattern that the star formation rate (SFR) density, increases by at least a factor of ~ 5 from z = 0 to 1, although the authors note highly discrepant UV- and radio-based SFR estimates. Their radio-based SFRs become more difficult to interpret at z > 1 where correcting for contamination by radio-loud active galactic nuclei (AGNs) comes at the price of rejecting luminous starbursts. While stacking radio images is a useful technique, accurate radio-based SFRs for z >> 1 galaxies require precise redshifts and extraordinarily high fidelity radio data to identify and remove accretion-related emission. Data were obtained at 1.4 GHz during 2003 to 2005 with the VLA in its B configuration, acquiring seven 3.125 MHz channels every 5 s at each of four intermediate frequencies. Data were obtained at six positions, spaced by 15 arcminutes, concentrating in the northern half of the EGS because of the proximity of 3C 295 (a 23 Jy source at 1.4 GHz). Around 18 hours of data were acquired for each of the field positions. Calibrated visibilities and associated weights were used to generate mosaics of 37 x 512<sup>2</sup> x 0.8 arcsec<sup>2</sup> pixel images to quilt the VLA's primary beam in each EGS field position. CLEAN boxes were placed tightly around all sources, and a series of IMAGR and CALIB tasks were run, clipping the UV data after subtracting CLEAN components generated by the third iteration of IMAGR. The central images from each of the pointings were then knitted together using FLATN, ignoring data beyond the primary beam's half-power point, to produce a large mosaic. The synthesized beam is circular, with a FWHM of ~ 3.8 arcseconds. To define a sample of radio sources, the authors searched signal-to-noise ratio (S/N) images using the SAD detection algorithm, emulating the technique described by Biggs & Ivison (2006, MNRAS, 371, 963). Sources with >= 4-sigma peaks were fitted with two-dimensional Gaussians using JMFIT, and those with >- 5-sigma peaks that survived were fitted in total intensity. Sources with sizes equal to or smaller than the restoring beam were considered unresolved. No correction is made for bandwidth smearing in the catalog; this is a small effect (~ 5%) given the mosaicking strategy and the use of the B configuration. 38, 79, 171, 496, and 1123 sources are detected with 1.4 GHz flux densities >= 2000, >= 800, >= 320, >= 130 and >= 50 microJansky (uJy) [including the duplicate source mentioned above], where the 5-sigma detection limits at 130 and 50 uJy cover 0.73 and 0.04 deg<sup>2</sup>, respectively. Confusion is not an issue; the source density on an arcmin<sup>2</sup> scale is < 0.01 beam<sup>-1</sup>. This table was created by the HEASARC in July 2013 based on an electronic versions of the catalog described in the reference paper which was obtained as a FITS file from the first author's web site at <a href="http://www.roe.ac.uk/~rji/aegis20/">http://www.roe.ac.uk/~rji/aegis20/</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/amigps16gh
- Title:
- AMI Galactic Plane Survey 16-GHz Source Catalog
- Short Name:
- AMIGPS16GH
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Arcminute Microkelvin Imager (AMI) Galactic Plane Survey is a large-area survey of the outer Galactic plane to provide arcminute resolution (approximately 3 arcminutes) images at milli-Jansky (mJy) sensitivity in the centimeter-wave band. This table contains results from the first data release of the survey, consisting of 868 deg<sup>2</sup> of the Galactic plane, covering the area above 40 degrees Declination (corresponding to 76 to 170 degrees Galactic Longitude) between Galactic Latitudes of -5 to +5 degrees at a central frequency of 15.75 GHz (1.9 cm). The noise level in the survey is <~ 3mJy/beam away from bright sources. This table contains the source catalog of 3503 radio sources detected with peak flux densities at or greater than 5 sigma. In their paper, the authors describe in detail the drift-scan observations which have been used to construct the maps, including the techniques used for observing, mapping and source extraction, and summarize the properties of the finalized data sets. These observations constitute the most sensitive Galactic plane survey of large extent at centimeter-wave frequencies greater than 1.4 GHz. This table was originally ingested by the HEASARC in March 2013 based on the CDS Catalog J/MNRAS/429/3330 file catdr1.dat. It was updated in September 2013 using the latest data file from the CDS, which provided positions with improved precision. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atlasd2cpt
- Title:
- ATLargeAreaSurvey(ATLAS)CDF-S&ELAIS-S11.4-GHzDR2ComponentsCatalog
- Short Name:
- ATLASD2CPT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 microJy 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 .
- ID:
- ivo://nasa.heasarc/atlascscpt
- Title:
- AT Large Area Survey (ATLAS) CDF-S/SWIRE 1.4-GHz Components Catalog
- Short Name:
- ATLASCSCPT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 deg<sup>2</sup> 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 .
- ID:
- ivo://nasa.heasarc/atlascsid
- Title:
- AT Large Area Survey (ATLAS) CDF-S/SWIRE ID and Classification Catalog
- Short Name:
- ATLASCSID
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the first results from the Australia Telescope Large Area Survey (ATLAS), which consists of deep radio observations of a 3.7 deg<sup>2</sup> 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 (see the companion table ATLASCSCPT), corresponding to 726 distinct radio sources, nearly all of which are identified with SWIRE sources. 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 726 radio sources and their cross-identifications at optical and infrared wavelengths which were given in Table 6 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. his table was created by the HEASARC in August 2012 based on CDS Catalog J/AJ/132/2409 file table6.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atlas5p5gh
- Title:
- AT Large Area Survey (ATLAS) E-CDF-S 5.5-GHz Components Catalog
- Short Name:
- ATLAS5P5GH
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Star-forming galaxies are thought to dominate the sub-mJy radio population, but recent work has shown that low-luminosity active galactic nuclei (AGNs) can still make a significant contribution to the faint radio source population. Spectral indices are an important tool for understanding the emission mechanism of the faint radio sources. The authors have observed the extended Chandra Deep Field South at 5.5 GHz using a mosaic of 42 pointings with the Australia Telescope Compact Array (ATCA). Their image reaches an almost uniform sensitivity of ~ 12 microJy (uJy) rms over 0.25 deg<sup>2</sup> with a restoring beam of 4.9 arcsec x 2.0 arcsec, making the ATLAS 5.5-GHz survey one of the deepest 6-cm surveys to date. This table contains the 5.5 GHz catalog of 142 source components corresponding to the 123 sources in this field: the source counts from this field are discussed in the reference paper. This table was created by the HEASARC in February 2013 based on the electronic version of Table 1 from the reference paper which was obtained from the MNRAS web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atlas2p3gh
- Title:
- ATLargeAreaSurvey(ATLAS)ELAIS-S1&CDF-S2.3-GHzSourceCatalog
- Short Name:
- ATLAS2P3GH
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Australia Telescope Large Area Survey (ATLAS) aims to image a 7 deg<sup>2</sup> 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 <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/544/A38">CDS Catalog J/A+A/544/A38</a> file spix_pub.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atlasescpt
- Title:
- AT Large Area Survey (ATLAS) ELAIS-S1/SWIRE 1.4-GHz Components Catalog
- Short Name:
- ATLASESCPT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from the Australia Telescope Large Area Survey (ATLAS), and consists of sensitive (1 sigma < 30 uJy) 1.4-GHz radio observations of a 3.9 deg<sup>2</sup> field centered on the European Large Area ISO Survey S1 (ELAIS-S1) region, largely coincident with infrared observations of the Spitzer Wide-Area Infrared Extragalactic (SWIRE) Survey. In their paper, the authors describe the observations and calibration, source extraction, and cross-matching to infrared sources. A total of 1366 radio components are identified, corresponding to 1276 distinct radio sources, 1183 of which are matched with infrared sources in the companion table ATLASESID. The authors have discovered 31 radio sources with no infrared counterpart at all, adding to the class of Infrared-Faint Radio Sources. The radio observations where made on 27 separate days in 2004 and 2005 with the Australia Telescope Compact Array (ATCA) with a total net integration time of 231 hours. as described in detail in Section 2.1 and Tables 1 and 2 of the reference paper. The observations were made in a mosaic of 20 overlapping pointings, where pointings 1-12 have net integration times of 10.5 hours per pointing and pointings 13-24 have net integration times of 13.5 hours per pointing. All observations were made with two 128-MHz bands, centered on frequencies of 1.34 and 1.43 GHz. After editing, the predicted noise level is 22 uJy in the center of the mosaic. Toward the image edges, the noise level increases due to primary beam attenuation. This table contains the list of 1366 radio components given in Table 4 of the reference paper. The authors define a radio 'component' as a region of radio emission which is best defined as a Gaussian. Close radio doubles are very likely to be best represented by two Gaussians and are therefore deemed to consist of two components. Single or multiple components are called a radio source if they are deemed to belong to the same object. This table was created by the HEASARC in August 2012 based on CDS Catalog J/AJ/135/1276 file table4.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atlasesid
- Title:
- AT Large Area Survey (ATLAS) ELAIS-S1/SWIRE ID and Classification Catalog
- Short Name:
- ATLASESID
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from the Australia Telescope Large Area Survey (ATLAS), and consists of sensitive (1 sigma < 30 uJy) 1.4-GHz radio observations of a 3.9 deg<sup>2</sup> field centered on the European Large Area ISO Survey S1 (ELAIS-S1) region, largely coincident with infrared observations of the Spitzer Wide-Area Infrared Extragalactic (SWIRE) Survey. In their paper, the authors describe the observations and calibration, source extraction, and cross-matching to infrared sources. A total of 1366 radio components are identified, corresponding to 1276 distinct radio sources, 1183 of which are matched with infrared sources in the present table. The authors have discovered 31 radio sources with no infrared counterpart at all, adding to the class of Infrared-Faint Radio Sources. The radio observations where made on 27 separate days in 2004 and 2005 with the Australia Telescope Compact Array (ATCA) with a total net integration time of 231 hours, as described in detail in Section 2.1 and Tables 1 and 2 of the reference paper. The observations were made in a mosaic of 20 overlapping pointings, where pointings 1-12 have net integration times of 10.5 hours per pointing and pointings 13-24 have net integration times of 13.5 hours per pointing. All observations were made with two 128-MHz bands, centered on frequencies of 1.34 and 1.43 GHz. After editing, the predicted noise level is 22 uJy in the center of the mosaic. Toward the image edges, the noise level increases due to primary beam attenuation. This table contains the list of 1276 radio sources and their cross-identifications at optical and infrared wavelengths which were given in Table 5 of the reference paper. The authors define a radio 'component' as a region of radio emission which is best defined as a Gaussian. Close radio doubles are very likely to be best represented by two Gaussians and are therefore deemed to consist of two components. Single or multiple components are called a radio source if they are deemed to belong to the same object. This table was created by the HEASARC in August 2012 based on CDS Catalog J/AJ/135/1276 file table5.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atlasspecz
- Title:
- ATLargeAreaSurvey(ATLAS)SpectroscopicClasses&RedshiftsCatalog
- Short Name:
- ATLASSPECZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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<sup>-1</sup> rms over the entire region with first data release currently reaching ~ 30 uJy beam<sup>-1</sup> 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 H<sub>0</sub> = 70 km s<sup>-1</sup> Mpc<sup>-1</sup>, Omega<sub>M</sub> = 0.3 and Omega<sub>Lambda</sub> = 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 .
- ID:
- ivo://nasa.heasarc/atcdfsss82
- Title:
- Australia Telescope Chandra Deep Field-South and SDSS Stripe 82 20-GHz Sources
- Short Name:
- ATCDFSSS82
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 deg<sup>2</sup> 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 alpha<sub>1.4</sub><sup>20</sup> < -0.5) and 45% have flat or inverted spectra (alpha<sub>1.4</sub><sup>20</sup> >= -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 (alpha<sub>1.4</sub><sup>20</sup> >= 0.0) sources, 10 have clearly defined peaks in their spectra with alpha<sub>1.4</sub><sup>5.5</sup> > 0.15 and alpha<sub>9</sub><sup>18</sup> < -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 .
- ID:
- ivo://nasa.heasarc/atcaadfs20
- Title:
- Australia Telescope Compact Array AKARI Deep Field South 20-cm Source Catalog
- Short Name:
- ATCAADFS20
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The results of a deep radio survey at a wavelength of 20 cm are reported for a region containing the AKARI Deep Field South (ADF-S) near the South Ecliptic Pole (SEP), using the Australia Telescope Compact Array (ATCA). The survey (hereafter referred to as the ATCA-ADFS survey) has 1-sigma detection limits ranging from 18.7 to 50 microJansky per beam (uJy/beam, over an area of ~1.1 deg<sup>2</sup>, and ~2.5 deg<sup>2</sup> to lower sensitivity. The observations, data reduction and source count analysis are presented in the paper, along with a description of the overall scientific objectives, and a catalog containing 530 radio sources detected with a resolution of 6.2 x 4.9 arcseconds (contained herein). The AKARI Deep Field South survey was primarily made in the far-infrared at wavelengths of 65, 90, 140, 160 micron (um) over a 12 deg<sup>2</sup> area with the AKARI Far-Infrared Surveyor (FIS) instrument, with shallower mid-infrared coverage at 9 and 18 um using the AKARI Infrared Camera (IRC) instrument. In addition to the wide survey, deeper mid-infrared pointed observations, using the IRC, covering ~0.8 deg<sup>2</sup> and reaching 5-sigma sensitivities of 16, 16, 74, 132, 280 and 580 uJy at 3.2, 4.6, 7, 11, 15 and 24 um, respectively, were also carried out. The radio observations were collected over a 13 day period in 2007 July using the ATCA operated at 1.344 and 1.432 GHz. The total integration time for the 2007 observations was 120 hours. The 2007 data were augmented with a further deep observation made in 2008 December over five nights towards a single pointing position at the ADF-S, which lay just off center of the larger ATCA-ADFS field reported here. This added a further 50 h of integration time. The data were processed in exactly the same way as that from the 2007 observing sessions. Note that in the terminology of the authors, a radio component is described as a region of radio emission represented by a Gaussian shaped object in the map. Close radio doubles are represented by two Gaussians and are deemed to consist of two components, which make up a single source. A selection of radio sources with multiple components is shown in Fig. 3 of the reference paper. This table was created by the HEASARC in November 2013 based on CDS Catalog J/MNRAS/427/1830 file table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atesp1p4gh
- Title:
- Australia Telescope ESO Slice Project 1.4-GHz Source Catalog
- Short Name:
- ATESP1P4GH
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Australia Telescope ESO Slice Project (ATESP) survey is a radio survey which was accomplished with the Australia Telescope Compact Array (ATCA) at 1.4 GHz over the region covered by the ESO Slice Project (ESP: Vettolani et al. 1997, A&A, 325, 954) galaxy redshift survey. This 26-degree<sup>2</sup> region is centered at Declination -40 degrees, and ranges in RA from 22<sup>h</sup> 30<sup>m</sup> to 01<sup>h</sup> 15<sup>m</sup>. The ATESP survey consisted of 16 radio mosaics with 8 x 14 arcseconds resolution and uniform sensitivity (1 sigma noise level of ~ 79 microJansky) over the whole area of the ESP redshift survey. According to the reference paper, the final 6-sigma ATESP catalog contained 2960 sources down to a detection limit of ~ 0.5 mJy (6 sigma), 1402 of which are sub-mJy sources, and 189 of which are multiple sources (168 doubles, 19 triples and 2 quadruples). This table contains the list of 6-sigma or more sources detected in the ATESP survey. For composite sources with multiple components, the individual components each have entries in this table, and there is also an entry for the entire source. Based on the numbers quoted above, this would imply that there should be (2960 + 2*168 + 3*19 + 4*2) = 3361 entries in this table. The HEASARC notes that there are actually 3370 entries in the CDS version of this table that the present table is based on, 169 of which are doubles, 19 triples and 2 quadruples, implying that this version has 2967 sources, slightly more than the number quoted in the reference paper. This table was created by the HEASARC in November 2012 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/63">CDS Catalog VIII/63</a> file atesp.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/at2fglus
- Title:
- Australia Telescope 2FGL Unassociated Sources Radio Source Catalog
- Short Name:
- AT2FGLUS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors report results of the first phase of observations with the Australia Telescope Compact Array (ATCA) at 5 and 9 GHz of the fields around 411 gamma-ray sources having declinations less than +10 degrees which were detected by the Fermi Gamma-ray Space Telescope, but marked as unassociated in the 2nd Fermi Large-Area Telescope (2FGL) Catalog (available at the HEASARC as the FERMILPSC table). They have detected 424 radio sources with flux densities in the range from 2 mJy to 6 Jy in the fields of 283 gamma-ray sources within their gamma-ray position error ellipses (drawn to cover the area of 99 per cent probability of their localization). Of these, 146 objects were detected in both 5- and 9-GHz bands. The authors found 84 sources with spectral indices flatter than -0.5 in their sample. The majority of detected sources are weaker than 100 mJy and for this reason were not found in previous surveys. Approximately 1/3 of this sample, 128 objects, have the probability of being associated which is more than 10 times the probability of their being a background source found in the vicinity of the gamma-ray object by chance. This table contains the catalog of positions of these radio sources, estimates of their flux densities and their spectral indices, when available. This table was created by the HEASARC in July 2013 based on the electronic versions of Tables 1, 2 and 3 from the reference paper which were obtained from the MNRAS web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/at20gharc
- Title:
- Australia Telescope 20-GHz (AT20G) High-Angular Resolution Catalog
- Short Name:
- AT20GHARC
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 .