- 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 .
- ID:
- ivo://nasa.heasarc/at20g
- Title:
- Australia Telescope 20-GHz (AT20G) Survey Catalog
- Short Name:
- AT20G
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Australia Telescope 20-GHz Survey (AT20G) is a blind radio survey carried out at 20 GHz with the Australia Telescope Compact Array (ATCA) from 2004 to 2008, and covers the whole sky south of declination 0 degrees. The AT20G source catalogue presented here is an order of magnitude larger than any previous catalogue of high-frequency radio sources, and includes 5890 sources above a 20-GHz flux-density limit of 40 mJy. All AT20G sources have total intensity and polarisation measured at 20 GHz, and most sources south of declination -15 degrees also have near-simultaneous flux-density measurements at 5 and 8 GHz. A total of 1559 sources were detected in polarised total intensity at one or more of the three frequencies. The completeness of the AT20G source catalog is 91% above 100 mJy/beam and 79% above 50 mJy/beam in regions south of Declination -15 degrees. North of -15 degrees, some observations of sources between 14 and 20 hours in RA were lost due to bad weather and could not be repeated, so the catalog completeness is lower in this region. Each detected source was visually inspected as part of the authors' quality control processs, and so the reliability of the final catalog is essentially 100%. This table was created by the HEASARC in March 2010 based on the CDS Catalog J/MNRAS/402/2403/ file at20gcat.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/at20gbss
- Title:
- Australia Telescope 20-GHz Survey Bright Source Sample
- Short Name:
- AT20GBSS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 S<sub>20GHz</sub> > 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 <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/384/775">CDS Catalog J/MNRAS/384/775</a> files table2.dat and table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/athdfs3frq
- Title:
- Australia Telescope Hubble Deep Field-South 2.5, 5.2 and 8.7-GHz Source Catalog
- Short Name:
- ATHDFS3FRQ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 microJy 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) = 22<sup>h</sup> 33<sup>m</sup> 25.96<sup>s</sup>, Dec (J2000.0) = -60<sup>o</sup> 38' 09.0" (2.5 GHz), and RA (J2000.0) = 22<sup>h</sup> 32<sup>m</sup> 56.22<sup>s</sup>, Dec (J2000.0) = -60<sup>o</sup> 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 .
- ID:
- ivo://nasa.heasarc/athdfsccat
- Title:
- Australia Telescope Hubble Deep Field-South Combined Source Catalog
- Short Name:
- ATHDFSCCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 microJy 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) = 22<sup>h</sup> 33<sup>m</sup> 25.96<sup>s</sup>, Dec (J2000.0) = -60<sup>o</sup> 38' 09.0". The observations at 5.2 and 8.7 GHz consist of single pointings centered on RA (J2000.0) = 22<sup>h</sup> 32<sup>m</sup> 56.22<sup>s</sup>, Dec (J2000.0) = -60<sup>o</sup> 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 .
- ID:
- ivo://nasa.heasarc/athdfs1p4g
- Title:
- Australia Telescope Hubble Deep Field-South 1.4-GHz Source Catalog
- Short Name:
- ATHDFS1P4G
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 microJy 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) = 22<sup>h</sup> 33<sup>m</sup> 25.96<sup>s</sup>, Dec (J2000.0) = -60<sup>o</sup> 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 .
- ID:
- ivo://nasa.heasarc/athdfsoid
- Title:
- Australia Telescope Hubble Deep Field-South Optical Identifications Catalog
- Short Name:
- ATHDFSOID
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Australia Telescope Hubble Deep Field-South (ATHDF-S) survey of the Hubble Deep Field-South (HDF-S) reaches sensitivities of ~ 10 microJy (uJy) 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: <pre> 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. </pre> 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 .
- ID:
- ivo://nasa.heasarc/atlgds2p1g
- Title:
- Australia Telescope Local Group Dwarf Spheroidals 2.1-GHz Components Catalog
- Short Name:
- ATLGDS2P1G
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Dwarf spheroidal (dSph) galaxies are key objects in near-field cosmology, especially in connection to the study of galaxy formation and evolution at small scales. In addition, dSphs are optimal targets to investigate the nature of dark matter. However, while we begin to have deep optical photometric observations of the stellar population in these objects, little is known so far about their diffuse emission at any observing frequency, and hence on thermal and non-thermal plasma possibly residing within dSphs. In this paper, the authors present deep radio observations of six local dSphs performed with the Australia Telescope Compact Array (ATCA) at 16 cm wavelength (2100 MHz frequency). They mosaicked a region of radius of about 1 degree around three 'classical' dSphs (CDS), Carina, Fornax, and Sculptor, and of about half of degree around three 'ultrafaint' dSphs (UDS), Bootes II, Segue 2, and Hercules. The rms noise level is below 0.05 mJy for all the maps. The restoring beams full width at half-maximum (FWHM) ranged from (4.2 arcseconds by 2.5 arcseconds) to (30.0 arcseconds by 2.1 arcseconds) in the most elongated case. A catalog, including the 1392 sources detected in the six dSph fields, is presented here. In the reference paper, the main properties of the background sources are discussed, with the positions and fluxes of the brightest objects compared with the FIRST, NVSS, and SUMSS observations of the same fields. The observed population of radio emitters in these fields is dominated by synchrotron sources.The authors have computed the associated source number counts at 2 GHz down to fluxes of 0.25 mJy, which prove to be in agreement with AGN count models. The observations presented in this paper were performed during 2011 July. The project was allocated a total of 123 h of ATCA observing time. The spectral setup included the simultaneous observation of a 2-GHz-wide band centered at 2100 MHz with a 1 MHz spectral resolution for continuum observations (recording all four polarization signals). The mapping of the three CDS required a 19 field-mosaic with a total on-source integration time of about 1 hour per field. For Bootes II and Hercules, a 7 field-mosaic with an on-source integration time of about 2 hours per field was chosen, while Segue 2, due to its smaller size,was imaged with a 3 field-mosaic with about 4 hours per field of integration time (with the purpose of maximizing the sensitivity). More precisely, a total of 16.5, 15.0, 17.0, 13.0, 10.9, and 9.6 hours were spent on-source for Carina, Fornax, Sculptor, Bootes II, Hercules, and Segue 2, respectively. The nominal rms sensitivity in each panel for the actual observing time was 36, 38, 35, 25, 28, and 20 microJy for Carina, Fornax, Sculptor, Bootes II, Hercules, and Segue 2, respectively. See Table 1 of the reference paper for the details of the average restoring beam parameters across all mosaic panels for each field of view (FoV). The authors used two automated routines for source extraction and cataloging, which are provided by the SEXTRACTOR package (Bertin & Arnouts 1996, A&AS, 117, 393) and the task SFIND in MIRIAD. In these maps, SFIND and SEXTRACTOR give nearly identical results for astrometry (number of sources and positions), once the threshold parameters in SEXTRACTOR are tuned (the authors found a threshold typically slightly above 5 sigma). The mismatch in positions is random, and about 1 arcsecond on average for all FoVs. This value can be taken as an estimate of the positional accuracy. Photometry on the other hand, gave quite different results for some sources: in the catalog, the authors used the results from SFIND since this was specifically written to analyze radio images, accounting for artifacts and sidelobes. The number of sources in each dSph FoV is reported in Table 2 of the reference paper. Radio sources can be made up of different components. To decide whether nearby sources are separated sources or components of a single source, the authors visually inspected all the fields where either the angular distance, theta, between sources was < 1 arcminute, or the criterion of Magliocchetti et al. (1998, MNRAS, 300, 257: theta < 100 arcseconds x sqrt[S<sub>peak</sub>/10 mJy]), was satisfied. A more detailed study of the 178 possible multiple sources will be reported in a future paper by these authors. This table was created by the HEASARC in June 2015 based on an electronic version of the source components catalog (Table 4 of the reference paper) which was obtained from the MNRAS web site. In Section 4 of the reference paper, the authors state that they "found 1835 entries in the catalog corresponding to a total of 1392 extracted sources with 178 cases being (possibly) multiple component sources". We note that the table downloaded from the MNRAS web site and used as the basis for this current HEASARC table actually contained only 1834 entries, The reason for this small discrepancy is not known. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/atlbs1p4gh
- Title:
- Australia Telescope Low-Brightness Survey Source Catalog
- Short Name:
- ATLBS1P4GH
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 (uJy/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 .
- ID:
- ivo://nasa.heasarc/atpmncat
- Title:
- Australia Telescope-PMN Catalog of Southern Radio Sources
- Short Name:
- ATPMNCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a source catalog of 9040 radio sources derived from high-resolution observations of a selection of 8385 Parkes-MIT-NRAO (PMN) sources made with the Australia Telescope Compact Array (ATCA). The catalog lists flux density and structural measurements at 4.8 and 8.6 GHz, derived from observations of all PMN sources in the declination range -87 degrees < Dec < -38.5 degrees (exclusive of galactic latitudes |b| < 2 degrees) with PMN flux density S<sub>4850</sub> > 70mJy (> 50 mJy south of Dec = -73 degrees). The authors assess the quality of the data, which was gathered in the 1992-1994 time period, and the resulting source parameters. They describe the population of catalogued sources, and compare it to samples from complementary catalogs. In particular, they find 122 radio sources with highly probable association with gamma-ray sources observed by the orbiting Fermi Large Area Telescope (LAT), and 11 more radio sources with possible associations with Fermi LAT sources. This Australia Telescope PMN (ATPMN) catalog lists the source measurements of flux density, position and structure of a selection of sources from the PMN catalog. Each catalog entry corresponds to a discrete source observed by the ATCA. In many cases, a single PMN source yields several ATPMN sources. Apart from the name of the parent PMN source, there is no indication of physical association: multiple sources in the one field may be aligned by chance, or may be components of the one object. This catalog contains the following information for each source: position; the flux density at 4.8 and 8.6 GHz; uncertainties in each flux density; the source size modelled as an ellipse (major axes, minor axes, position angle) of the best fit for a Gaussian brightness distribution; the spectral index computed between 4.8 and 8.6 GHz; the uncertainty in the spectral index; a code denoting the epoch of the observation. In the table as given in the original reference, the positions were given with varying degrees of precision, from 0.001 to 1 second of time in RA and from 0.01 to 1 arcsecond in Declination. The authors state in Section 4 of the reference paper that the error in a position coordinate is less than 10 times the final digit given in the coordinate. The positions as displayed in this table do not reflect this system: e.g., a Dec value displayed as '-79 58 34.00' may have been given in the original table as '-79 58 34.00' or '-79 58 34.0' or '-79 58 34'. To recover this information about positional precision the HEASARC has created two additional parameters ra_accuracy and dec_accuracy which list the number of digits after the decimal point given in the original table for the RA and Dec, respectively. Thus, if ra_accuracy = 3, the RA was given to a precision of 0.001 s in the original table, implying that the actual error in RA was less than 10 * 0.001 = 0.01 s. This table was created by the HEASARC in July 2012 based on CDS Catalog J/MNRAS/422/1527 file atpmncat.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/askapbeta
- Title:
- BETA Pilot Multi-Epoch Continuum Survey of Spitzer SPT Deep Field
- Short Name:
- ASKAPBETA
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Boolardy Engineering Test Array (BETA) is a 6 x 12m-dish interferometer and the prototype of the Australian Square Kilometre Array Pathfinder (ASKAP), equipped with the first generation of ASKAP's phased array feed (PAF) receivers. These facilitate rapid wide-area imaging via the deployment of simultaneous multiple beams within an ~30 deg<sup>2</sup> field of view. By cycling the array through 12 interleaved pointing positions and using nine digitally formed beams, the authors have effectively mimicked a traditional 1 hours x 108 pointing survey, covering ~150 deg<sup>2</sup> over 711-1015 MHz in just 12 hours of observing time. Three such observations were executed over the course of a week. The authors verified the full bandwidth continuum imaging performance and stability of the system via self-consistency checks and comparisons to existing radio data. The combined three epoch image has arcminute resolution and a 1-sigma thermal noise level of 375 µJy/beam, although the effective noise is a factor of ~3 higher due to residual sidelobe confusion. From this, the authors have derived a catalog of 3,722 discrete radio components, using the 35% fractional bandwidth to measure in-band spectral indices for 1037 of them. A search for transient events reveals one significantly variable source within the survey area. The survey covers approximately two-thirds of the Spitzer South Pole Telescope (SPT) Deep Field. This pilot project demonstrates the viability and potential of using PAFs to rapidly and accurately survey the sky at radio wavelengths. The target field was observed with BETA on three separate occasions as part of the commissioning and verification of the instrument. The telescope delivers 304 MHz of instantaneous bandwidth and for these observations the sky frequency range was 711-1015 MHz, corresponding to a fractional bandwidth of 35%. The data were captured with a frequency resolution of 18.5 kHz, using 16,416 frequency channels across the band. The PYBDSM source finder was used to extract a component catalog from the deep mosaic image formed from a combination of all epochs and sub-bands. Components were fit to islands of emission that had a peak brightness of >5 sigma and an island boundary threshold of >3 sigma, where sigma is the local estimate of the background noise level. Component spectral indices were assigned by matching positions at which spectral indices were successfully fit (Section 4.5 of the reference paper). Following the excision of some spurious detections at the noisy edge of the mosaic, the final catalog contains 3,722 components, 1,037 of which have in-band spectral index measurements. This table was created by the HEASARC in March 2017 based on CDS Catalog J/MNRAS/457/4160 file table3.dat, the list of source components found in the ASKAP-BETA Survey covering two-thirds of the Spitzer SPT Deep Field. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/bootesdf
- Title:
- Bootes Deep Field WSRT 1.4-GHz Source Catalog
- Short Name:
- Bootes
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This radio source catalog is the result of deep (16x12 hour) Westerbork Synthesis Radio Telescope (WSRT) observations of the approximately 7 square degree Bootes Deep Field, centered at an RA and Declination (J2000) of 14 hr 32 min 5.75 sec, +34 deg 16 arcmin 47.5 arcsec. The survey consisted of 42 discrete pointings, with enough overlap to ensure a uniform sensitivity across the entire field, and with a limiting sensitivity of 28 microJansky (1 sigma rms). The catalog consists of 3172 distinct sources detected with a significance of 5 sigma or greater, of which 316 are resolved by the 13 x 27 arcsec beam. This database table was created by the HEASARC in December 2001 based on the a data file obtained from the authors' FTP site (no longer available). It was modified slightly in March 2011 (using the CDS data file <a href="ftp://cdsarc.u-strasbg.fr/pub/cats/J/AJ/123/1784/catalog.dat">ftp://cdsarc.u-strasbg.fr/pub/cats/J/AJ/123/1784/catalog.dat</a>) to make the source names adhere to the naming convention of the Dictionary of Nomenclature of Celestial Objects. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/boof153mhz
- Title:
- Bootes Field GMRT 153-MHz Source Catalog
- Short Name:
- BOOF153MHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors obtained deep, high-resolution radio interferometric observations at 153 MHz to complement the extensively studied NOAO Bootes field. In their paper, they provide a description of the observations, data reduction and source catalog construction. From their single-pointing GMRT observation of ~12 hours, they obtained a high-resolution (26" x 22") image of ~11.3 square degrees, fully covering the Bootes field region and beyond. The image has a central noise level of ~1.0 mJy beam<sup>-1</sup>, which rises to 2.0 - 2.5 mJy beam<sup>-1</sup> at the field edge, placing it amongst the deepest ~150 MHz surveys to date. The catalog of 598 extracted sources is estimated to be ~92% complete for > 10 mJy sources, while the estimated contamination by false detections is < 1%. The low rms positional uncertainty of 1.24" facilitates accurate matching against catalogs at optical, infrared and other wavelengths. Differential source counts were determined down to < ~10 mJy. The authors find no evidence for flattening of the counts towards lower flux densities as observed in deep radio surveys at higher frequencies, suggesting that their catalog is dominated by the classical radio-loud AGN population that explains the counts at higher flux densities. Combination with available deep 1.4 GHz observations yields an accurate determination of spectral indices for 417 sources down to the lowest 153 MHz flux densities, of which 16 have ultra-steep spectra with spectral indices below -1.3. The authors confirm that flattening of the median spectral index towards low flux densities also occurs at this frequency. The detection fraction of the radio sources in the NIR K<sub>s</sub>-band is found to drop with radio spectral index, which is in agreement with the known correlation between spectral index and redshift for brighter radio sources. This table contains the list of 598 153-MHz sources detected in the GMRT observation and their properties at this frequency. There are a number of other tables of objects in the Bootes field made at other frequencies: <pre> HEASARC Table | Title | Reference BOOTESDF | 1.4GHz imaging of the Bootes field | de Vries+ 2002,AJ,123,1784 LALABOOCXO | LALA Bootes field X-ray source catalog | Wang+ 2004,AJ,127,213 --- | Faint radio sources in NOAO Bootes field | Wrobel+ 2005,AJ,130,923 --- | 16um sources in the NOAO Bootes field | Kasliwal+ 2005,ApJ,634,L1 XBOOTES | X-ray survey of the NDWFS Bootes field | Kenter+ 2005,ApJS,161,9 XBOOTESOID | Optical counterparts in the NDWFS Bootes | Brand+ 2006,ApJ,64,140 | field | </pre> This table was created by the HEASARC in December 2011 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/535/A38">CDS Catalog J/A+A/535/A38</a> file table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/at20gbspol
- Title:
- Bright Extra-Galactic AT20G Sources Polarizations Catalog
- Short Name:
- AT20GBSPOL
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains polarization data for 180 extragalactic sources extracted from the Australia Telescope 20-GHz (AT20G) survey catalog and observed with the Australia Telescope Compact Array (ATCA) during a dedicated, high sensitivity run (sigma<sub>P</sub> ~ 1 mJy). For the sake of completeness, the authors extracted the polarization information for seven extended sources from the 9-yr Wilkinson Microwave Anisotropy Probe co-added maps at 23 GHz. The full sample of 187 sources constitutes a ~ 99% complete sample of extragalactic sources brighter than S<sub>20GHz</sub> = 500 mJy at the selection epoch with Declination below -30<sup>o</sup>. The sample has a 91.4% detection rate in polarization at ~ 20 GHz (94% if considering the sub-sample of point-like sources). The authors have measurements also at 4.8 and 8.6 GHz within ~1 month of the 20-GHz observations for 172 sources so as to reconstruct the spectral properties of the sample in total intensity and in polarization: 143 of them have a polarization detection at all three frequencies. The authors find that there is no statistically significant evidence of a relationship either between the fraction of polarization and frequency or between the fraction of polarization and the total intensity flux density. This indicates that Faraday depolarization is not very important above 4.8 GHz and that the magnetic field is not substantially more ordered in the regions dominating the emission at higher frequencies (up to 20 GHz). The authors estimate the distribution of the polarization fraction and the polarized flux density source counts at ~20 GHz. The selection of the sample was based on the list of confirmed AT20G sources available at the epoch of these observations (2006 October). The authors selected all objects with flux density S<sub>20GHz</sub> > 500 mJy and Declination below -30<sup>o</sup>, excluding the Galactic plane region (|b| <= 1.5o^) and the Large Magellanic Cloud (LMC) region (inside a circle of 5.5<sup>o</sup> radius centered at RA =05:23:34.7 and Dec=-69:45:22 in J2000.0 coordinates). This resulted in a complete sample of 189 sources. The observations were taken on October 1, 2006 using the most compact hybrid configuration of ATCA, H75, excluding the data from the farthest antenna. The longest baseline of this configuration is 75 m, and its T-shape ensures adequate Fourier coverage for snapshots taken on a relatively small range of hour angles and at high elevation. In a number of cases, indicated by source_flags values of 's', 'f' or 'w', the highest frequency data is not at 18 GHz, but at 20 or 23 GHz. This table was created by the HEASARC in January 2015 based on the CDS Catalog J/MNRAS/436/2915 file table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cgpsngpcat
- Title:
- Canadian Galactic Plane Survey (CGPS) 1420-MHz Compact Source Catalog
- Short Name:
- CGPSNGPCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of compact sources of radio emission at 1420 MHz in the northern Galactic plane from the Canadian Galactic Plane Survey (CGPS). The catalog contains 72,758 compact sources with an angular size less than 3 arcminutes within the Galactic longitude range 52 < l<sub>II</sub> < 192 degrees down to a 5-sigma detection level of ~1.2 mJy. Linear polarization properties are included for 12,368 sources with signals greater than 4 x sigma<sub>QU</sub> in the CGPS Stokes Q and U images at the position of the total intensity peak. In the reference paper, the authors compare the CGPS flux densities with the catalogued flux densities in the Northern VLA Sky Survey (NVSS) catalog for 10,897 isolated unresolved sources with CGPS flux density greater than 4 mJy in order to search for sources that show variable flux density on timescales of several years. They identify 146 candidate variables that exhibit high fractional variations between the two surveys. In addition, they identify 13 candidate transient sources that have CGPS flux density above 10 mJy but that are not detected in the NVSS. In the CGPS, the Synthesis Telescope at the Dominion Radio Astrophysical Observatory (the DRAO ST) provided arcminute-resolution images of the radio continuum and atomic-hydrogen line emission of the northern Galactic Plane. The CGPS DRAO radio continuum observations provided images of Stokes I, Q, and U in four 7.5-MHz sub-bands spanning 35 MHz, centered on 1420 MHz. The observations were carried out in three phases beginning in 1995 and ending in 2009. The sky coverage of each phase and the observing dates are listed in Table 1 of the reference paper. The Galactic plane was covered with a width in Galactic latitude of 9 degrees, centered at b<sub>II</sub> = 1 degree to accommodate the warp of the Galactic disk. The longitude coverage was constrained by the southern Declination limit of ~20 degrees, the range that could be effectively imaged by a linear east-west synthesis telescope array. The Phase II observations included an extension to higher latitudes (b<sub>II</sub> = 17.5 degrees) over a restricted range of longitude. In this table, we present the CGPS 1420-MHz compact source catalog covering 1,464 square degrees and spanning a range of 140 degrees of Galactic longitude between 52 and 192 degrees. This table was created by the HEASARC in June 2017 based upon a machine-readable version of Table 2 from the reference paper that was obtained from the AJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cgrabs
- Title:
- Candidate Gamma-Ray Blazar Survey Source Catalog
- Short Name:
- CGRABS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have constructed a uniform all-sky survey of bright blazars, selected primarily by their flat radio spectra, that is designed to provide a large catalog of likely gamma-ray active galactic nuclei (AGNs). The defined sample, the Candidate Gamma-Ray Blazar Survey (CGRaBS) source catalog, has 1625 targets with radio and X-ray properties similar to those of the EGRET blazars, spread uniformly across the |b| > 10 degrees sky. They also report progress toward optical characterization of the sample; of objects with known red magnitude R < 23, 85% have been classified and 81% have measured redshifts. One goal of this program is to focus attention on the most interesting (e.g., high-redshift, high-luminosity, etc.) sources for intensive multi-wavelength study during the observations by the Large Area Telescope (LAT) on the Gamma-Ray Large-Area Space Telescope (GLAST) satellite observatory. This table was created by the HEASARC in April 2008 based on an electronic version of Table 2 of the reference paper obtained from the electronic ApJS web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/uc7c151mhz
- Title:
- 7C Catalog 151-MHz Survey Final Unified Source Catalog
- Short Name:
- UC7C151MHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a final unified catalog for the 7C survey at 151 MHz with a spatial resolution of 70 x 70cosec(Dec) arcsec<sup>2</sup>. This has been constructed by amalgamating the existing catalogs derived from individual fields imaged at this resolution and eliminating redundancy in regions of mutual overlap. This was a non-trivial procedure because the flux in multiple-component sources may be fitted differently on alternative images, owing, for example, to differences in local noise and beam distortion. The final catalog as published thus produced contains 43683 sources. (Note that the HEASARC removed one duplicate source entry for '7C 083231.6+262635' since it had two entries, which were identical except that in one the beam-fitted flux density S<sub>bf</sub> was 834 mJy/beam, while, in the other entry now removed, S<sub>bf</sub> was 840 mJy/beam). Separate final catalogs have been previously published for the 7C Galactic Plane 7CG survey (available as the HEASARC table GP7C151MHZ), and the lower-resolution survey of the low-declination strip 9<sup>h</sup> < RA < 16<sup>h</sup>, 20<sup>o</sup> < Dec < 35<sup>o</sup> (available as the HEASARC table LD7C151MHZ). The individual catalogs for about 40 of the 96 regions contributing to the total have already been published, together with full details of the methodology, in MNRAS or A&AS: <pre> Reference Region Lacy et al. 1995, MNRAS, 276, 614 92 Visser et al. 1995, A&AS, 110, 419 93 Pooley et al. 1998, MNRAS, 298, 637 94-96 Riley et al. 1999, MNRAS, 306, 31 1-33 </pre> and these data are also available via the MRAO website: <a href="http://www.mrao.cam.ac.uk/surveys/7C/">http://www.mrao.cam.ac.uk/surveys/7C/</a> Individual catalogs for the remaining 58 regions by Riley et al. (regions 34-91) were released electronically via the MRAO website in November 2001. These include a re-analysis of data originally published in rather a different parametrization by McGilchrist et al. 1990, MNRAS, 246, 110. The regions re-analyzed are those numbered 41, 44, 59, 60, 62 and 63 and they supersede McGilchrist's 1990 publication. The RA x Dec coverage, the average rms noise, the flux density of the faintest source listed and the completeness limit for each of the individual regions contributing to the final catalog are given in the table <a href="http://cdsarc.u-strasbg.fr/ftp/cats/J_MNRAS/382/1639/regions.dat">http://cdsarc.u-strasbg.fr/ftp/cats/J_MNRAS/382/1639/regions.dat</a>. For further details of the surveys and data analysis procedures please refer to the published papers referenced above and other references contained therein. This table was created by the HEASARC in October 2010 based on CDS table J/MNRAS/382/1639 files 7c.dat and regions.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rt9cc15ghz
- Title:
- 9C Continued 15-GHz Ryle Telescope Survey of VSA Fields Source Catalog
- Short Name:
- RT9CC15GHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The 9C (9th Cambridge) survey of radio sources with the Ryle Telescope at 15.2 GHz was set up to survey the fields of the cosmic microwave background telescope, the Very Small Array (VSA). In their first paper (Waldram et al. 2003, MNRAS, 342, 915), the authors described three regions of the survey, constituting a total area of 529 deg<sup>2</sup> to a completeness limit of ~ 25 mJy. In this follow-up, they present results from a series of deeper regions, constituting a total area of 115 deg<sup>2</sup> complete to ~ 10 mJy and of 29 deg<sup>2</sup> complete to ~ 5.5 mJy. The authors have investigated the source counts and the distributions of the 1.4 to 15.2 GHz spectral indices for these deeper samples. The whole catalog of 643 sources is contained in the present table. Down to their lower limit of 5.5 mJy, the authors detect no evidence for any change in the differential source count from the earlier fitted count above 25 mJy, n(S) = 51(S/Jy)<sup>-2.15</sup> Jy<sup>-1</sup> sr<sup>-1</sup>. They matched both their new and earlier catalogues with the NRAO VLA Sky Survey (NVSS) catalogue at 1.4 GHz and selected flux-limited samples at both 15 and 1.4 GHz. As they expected, they found that the proportions of sources with flat and rising spectra in the samples selected at 15 GHz are significantly higher than those in the samples selected at 1.4 GHz. In addition, for 15-GHz samples selected in three flux density ranges, they detect a significant shift in the median value of the 1.4 to 15.2 GHz spectral index: the higher the flux densities, the higher the proportions of sources with flat and rising spectra. In the area complete to ~ 10 mJy, the authors find five sources between 10 and 15 mJy at 15 GHz, amounting to 4.3 per cent of sources in this range, with no counterpart in the NVSS catalogue. This implies that, had they relied on the NVSS for locating their sources, they could have missed a significant proportion of them at low flux densities. These results illustrate the problems inherent in using a low-frequency catalog to characterize the source population at a much higher frequency and emphasize the value of a blind 15.2-GHz survey. This table was created in November 2010 based on CDS catalog J/MNRAS/404/1005 file 9c_cont.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rtv9c15ghz
- Title:
- 9C 15-GHz Ryle Telescope Survey of VSA Fields Source Catalog
- Short Name:
- RTV9C15GHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The fields chosen for the first observations of the cosmic microwave background (CMB) with the Very Small Array (VSA) have been surveyed with the Ryle Telescope at 15 GHz. The authors have covered three regions around RA = 00<sup>h</sup>20<sup>m</sup> and Dec = +30<sup>o</sup>, RA = 09<sup>h</sup>40m and Dec = +32<sup>o</sup> and RA = 15<sup>h</sup>40<sup>m</sup> and Dec = +43<sup>o</sup> (J2000.0), comprising an area of 520 deg<sup>2</sup>. There are 465 sources in this entire area which are above the estimated completeness limit of ~ 25 mJy, although a total of ~ 760 sources were detected, some as faint as 10 mJy. The prime motivation of this study was to define a catalog of the foreground sources that must be monitored by the VSA during its observations at 34 GHz. In particular, it provides a means of identifying GigaHertz peaked spectrum (GPS) sources, which are important for the study of radio source evolution, as well as being a significant foreground for CMB observations over a range of wavelengths. Since this will be a new and quite extensive survey, it was desgignated as '9C' or the Ninth Cambridge survey. For the purpose of this particular component of the 9C survey, the authors designated as a subset, 3 circular areas, VSA1, VSA2 and VSA3, defined by the properties listed in Table 2 of the reference paper and reproduced below: <pre> Field Centre J2000.0 Center B1950.0 Radius Area RA Dec RA Dec (degrees) (sq. degrees) VSA1 00 17 36.5 +30 16 39 00 15 00.0 +30 00 00 5.5 95.0 VSA2 09 40 57.7 +31 46 21 09 38 00.0 +32 00 00 6.0 113.0 VSA3 15 36 42.7 +43 20 11 15 35 00.0 +43 30 00 5.0 78.5 </pre> There are 242 sources which were both above the 25 mJy completeness limit and were in the 286.5 deg<sup>2</sup> contained within these 3 circular fields. These source were listed in 3 tables in the reference paper, Table 4 (VSA1), Table 5 (VSA2) and Table 6 (VSA3). These have been combined into this one HEASARC table, in which the HEASARC added a new parameter vsa_field, which is set to 1 for the VSA1 sources, 2 for the VSA2 sources, and 3 for the VSA3 sources. This table was created in November 2010 based on CDS catalog J/MNRAS/342/915 files table4.dat, table5.dat and table6.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gp7c151mhz
- Title:
- 7C(G) 151-MHz Northern Galactic Plane Survey Catalog
- Short Name:
- GP7C151MHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Results from a survey of the northern Galactic plane (at Declination >= 30<sup>o</sup> at 151 MHz made with the Cambridge Low Frequency Synthesis Telescope (CLFST) are presented in this table. This survey was designated the 7C(G) - i.e. the Galactic portion of the then-ongoing 7C surveys. The 7C(G) covers the regions 80<sup>o</sup> < l < 104<sup>o</sup> and 126<sup>o</sup> < l < 180<sup>o</sup>, for |b| <= 5.5<sup>o</sup>, and has some coverage to |b| ~ 9<sup>o</sup>, with a resolution of ~70 x70 cosec{delta} arcsec<sup>2</sup> (RA x Dec). The observations, data reduction and calibration of this survey are described in the reference paper, and the catalog of 6262 compact sources, with a completeness limit of ~ 0.25 Jy (250 mJy) over most of the survey region, is presented in this table. The catalog has an rms positional accuracy of better than 10 arcseconds, and the flux densities are tied to the scale of Roger, Bridle & Costain (1973, AJ, 78, 1030) with an accuracy of better than 10 per cent. This table was created by the HEASARC in October 2010 based on CDS table J/MNRAS/294/607 file 7cg.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ld7c151mhz
- Title:
- 7C 151-MHz Low-Declination Survey Catalog
- Short Name:
- LD7C151MHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 9<sup>h</sup> to 16<sup>h</sup>, and of Dec from 20<sup>o</sup> to 35<sup>o</sup>, with an angular resolution of 108 x 108cosec(Dec) arcsec<sup>2</sup>. 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 .
- ID:
- ivo://nasa.heasarc/north20cm
- Title:
- 20cm Radio Catalog
- Short Name:
- North20cm
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The 1.4-GHz Northern Sky Catalog - Version: 4 December 1991 This is the 20-cm Northern Sky Catalog of White, R. L. and Becker, R. H. (1992, Ap.J.Supp., in press) containing 30,239 sources detected from the Condon Greenbank images taken at 1.4 GHz over the declination range of -5 degrees to 82 degrees with a flux density limit of 100 mJy. This 20 cm catalog also contains the results of a cross-correlation with catalogs at 6 and 80 cm covering the northern sky between Dec=0 degrees and 70 degrees to give the spectral indices at three frequencies for about 20,000 sources. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/north6cm
- Title:
- 6cm Radio Catalog
- Short Name:
- North-6cm
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The NORTH6CM database is a catalog of 53,522 4.85-GHz sources generated by Becker, R. H., White, R. L., Edwards, A. L. 1991, ApJS 75, 1. It covers between 0 degrees and 75 degrees declination using observations taken with the NRAO Greenbank 300-ft telescope by Condon, Broderick and Seielstad (1989). The flux limit of the catalog is dependent on declination and ranges from approximately 40 mJy at 0 degrees to 20 mJy at 60 degrees. The source positions given in the catalog have a 95% confidence radius of approximately 50 arcsec. Spectral indices have been calculated for 29,051 sources which have counterparts in the Texas 365-MHz Northern Sky Survey. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/crates
- Title:
- CRATES Flat-Spectrum Radio Source Catalog
- Short Name:
- CRATES
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have assembled an 8.4 GHz survey of bright, flat-spectrum (alpha > -0.5) radio sources with nearly uniform extragalactic (|b| > 10 degrees) coverage for sources brighter than a 4.8 GHz flux density S_4.8GHz = 65 mJy. The catalog is assembled from existing observations (especially the Cosmic Lens All-Sky Survey, CLASS, and the Wright et al. PMN-CA survey), augmented by reprocessing of archival VLA and ATCA data and by new observations to fill in coverage gaps. The authors refer to this program as CRATES, the Combined Radio All-Sky Targeted Eight-GHz Survey. The resulting catalog provides precise positions, subarcsecond structures, and spectral indices for some 11,000 sources. The authors describe the morphology and spectral index distribution of the sample and comment on the survey's power to select several classes of interesting sources, especially high-energy blazars. Comparison of CRATES with other high-frequency surveys also provides unique opportunities for identification of high-power radio sources. This table contains 14467 entries, where each entry corresponds to an 8.4-GHz counterpart source (or absence thereof) to one of 11,131 4.8-GHz sources. The number of entries exceeds the number of 4.8-GHz sources because there are many cases in which there are multiple (from 2 - 20) 8.4-GHz counterparts to a single 4.8-GHz source. There are also 762 entries in which no 8.4-GHz counterpart was detected (morph_type = 'N'). This table was created by the HEASARC in August 2007 based on the electronic version of Table 5 obtained from the electronic ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rrs8c38mhz
- Title:
- 8C Revised Rees Survey 38-MHz Source Catalog
- Short Name:
- RRS8C38MHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a revised machine-readable source list for the Rees 38-MHz (or '8C') survey with improved positions and no redundancy. The Rees 38-MHz survey covers an area of about 1 sr north of declination +60 degrees. The angular resolution is 4.5 x 4.5 cosec(Dec) arcmin<sup>2</sup> and the limiting flux density over much of the survey area is about 1 Jy. Both of these figures were an improvement by nearly an order of magnitude on previous surveys at this frequency. Users of these data should consult and cite the original survey paper by Rees as primary reference (1990MNRAS.244..233R) with the present publication (1995MNRAS.274..447H) as a supplementary revision. The recommended style of reference is thus: "The revised Rees 38-MHz survey (Rees 1990, catalogue revised Hales et. al 1995)." In the Hales et al. (1995) paper, the authors aimed to improve the accuracy of the source positions to <~ 1 arcminute, so that a search radius smaller than the survey resolution of 4.5 arcminutes was practicable everywhere. Note that for interest the source list includes data on some sources at declinations lower than +60 degrees, but that the right ascension coverage is not complete below +60 degrees. This table was created in November 2010 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/31">CDS catalog VIII/31</a> file 8c.dat. 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/ami10c15gz
- Title:
- 10C Survey at 15.7 GHz Radio Source Catalog
- Short Name:
- AMI10C15GZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- In a previous paper (AMI Consortium 2011, MNRAS, 415, 2699: Paper I), the observational, mapping and source-extraction techniques used for the Tenth Cambridge (10C) Survey of Radio Sources were described. Here, the first results from the survey, carried out using the Arcminute Microkelvin Imager (AMI) Large Array (LA) at an observing frequency of 15.7 GHz, are presented. The survey fields cover an area of ~ 27 deg<sup>2</sup> to a flux-density completeness of 1 mJy. Results for some deeper areas, covering ~ 12 deg<sup>2</sup>, which are wholly contained within the total areas and complete to 0.5 mJy, are also presented. The completeness for both areas is estimated to be at least 93 per cent. The 10C survey is the deepest radio survey of any significant extent (>~ 0.2 deg<sup>2</sup>) above 1.4 GHz. The 10C source catalogue contains 1897 entries detected above a flux density threshold of > 4.62 sigma, and is available here and at the authors' web site <a href="http://www.mrao.cam.ac.uk/surveys/10C">http://www.mrao.cam.ac.uk/surveys/10C</a>. The source catalog has been combined with that of the Ninth Cambridge Survey to calculate the 15.7-GHz source counts. A broken power law is found to provide a good parametrization of the differential count between 0.5 mJy and 1 Jy. The measured source count has been compared with that predicted by de Zotti et al. (2005, A&A, 431, 893, and the model is found to display good agreement with the data at the highest flux densities. However, over the entire flux-density range of the measured count (0.5 mJy to 1 Jy), the model is found to underpredict the integrated count by ~ 30 per cent. Entries from the source catalog have been matched with those contained in the catalogues of the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-cm survey (both of which have observing frequencies of 1.4 GHz). This matching provides evidence for a shift in the typical 1.4-GHz spectral index to 15.7-GHz spectral index of the 15.7-GHz-selected source population with decreasing flux density towards sub-mJy levels - the spectra tend to become less steep. Automated methods for detecting extended sources, developed in Paper I, have been applied to the data; ~ 5 per cent of the sources are found to be extended relative to the LA-synthesized beam of ~ 30 arcsec. Investigations using higher resolution data showed that most of the genuinely extended sources at 15.7 GHz are classical doubles, although some nearby galaxies and twin-jet sources were also identified. This table was created by the HEASARC in August 2011 based on an electronic version of Table 1 of the reference paper which was obtained from the 10C Survey web site <a href="http://www.mrao.cam.ac.uk/surveys/10C/">http://www.mrao.cam.ac.uk/surveys/10C/</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/dixon
- Title:
- Dixon Master List of Radio Sources (Version 43)
- Short Name:
- Dixon
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table is the Dixon Master List of Radio Sources (Version 43, dated November 1981) which contains flux densities for known radio sources detected at a variety of frequencies. The Master List of Radio Sources was prepared by combining about thirty catalogs of radio sources that were available as of that date into a common format. Notice that this is a list of observations, not of individual sources, and that an entry in this table corresponds to an observation of a radio source at a particular frequency from a particular source catalog: also, no attempt was made by the author to use the same name for the same source, e.g., the source 3C 273 appears more than a dozen times under a variety of names such as PKS 1226+02, NRAO400, CTA 53, etc. This database table was recreated at the HEASARC in June 2005 after it was discovered that the positions had been incorrectly precessed. The original input table used for both the previous and current HEASARC Dixon tables was the 43rd version of the Master List, dated November 1981. It was obtained from the Colorado node of the Astrophysics Data System (ADS), the now-defunct HTTP link <adswww.colorado.edu/catalogs/rad_msl43.html>, and apparently was provided by D. E. Harris on or after 1991. Notice that the version of this table that is currently available at CDS (<a href="ftp://cdsarc.u-strasbg.fr/pub/cats/VII/2A">ftp://cdsarc.u-strasbg.fr/pub/cats/VII/2A</a>) is, according to Andernach (1989, Bull. Inf. Centre Donnees Stellaires, 37, 139), the 42nd edition (dated 1976) and has only 79493 entries compared to 84510 entries in the HEASARC table. 49 duplicate entries were removed from the HEASARC table in June 2019. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/kuehr
- Title:
- Extragalactic Radio Sources
- Short Name:
- Kuehr
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog is a compilation of 518 extragalactic radio sources with flux densities greater than 1 Jy at 5 GHz. It contains sources from the NRAO-MPI 5-GHz Strong Source Surveys and from re-observation at 5 GHz of sources found in the Parkes 2.7-GHz surveys. All sources were found in 9.811 sr covered by the two surveys. This is essentially the whole sky, excluding the galactic plane (latitudes less than 10 degrees) and the Magellanic Clouds. The catalog includes radio flux densities, radio positions, object classes, visual magnitudes, redshifts, and spectral indices. One duplicate entry was removed from the HEASARC implementation of this catalog in June 2019. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/first
- Title:
- Faint Images of the Radio Sky at Twenty cm (FIRST)
- Short Name:
- FIRST
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog comprises the Faint Images of the Radio Sky at Twenty cm (FIRST) Survey. The FIRST survey began in 1993, and covers the north and south Galactic caps. The present 14Dec17 version is derived from the 1993 through 2011 observations. The catalog covers a total of about 10,575 square degrees of sky (8,444 square degrees in the north Galactic cap and 2,131 square degrees in the south Galactic cap). See the coverage maps at <a href="http://sundog.stsci.edu/first/catalogs/readme_14dec17.html#coverage">http://sundog.stsci.edu/first/catalogs/readme_14dec17.html#coverage</a> for more details of the area covered. Both the northern and southern areas were chosen to coincide approximately with the area covered by the Sloan Digital Sky Survey (SDSS). The catalog is identical to the previous version of the catalog (14Mar04) except that it has more accurate data on which sources are not covered by the SDSS DR10 catalog. Approximately 1000 sources that were indicated as covered by DR10 in the previous version are now correctly marked as not covered. The source list, radio fluxes, etc., are all the same as the 14Mar04 version. In this version of the catalog, images taken in the the new EVLA configuration have been re-reduced using shallower CLEAN thresholds in order to reduce the "CLEAN bias" in those images. Also, the EVLA images are not co-added with older VLA images to avoid problems resulting from the different frequencies and noise properties of the configurations. That leads to small gaps in the sky coverage at boundaries between the EVLA and VLA regions. As a result, the area covered by this release of the catalog is about 60 square degrees smaller than the earlier release of the catalog (13Jun05), and the total number of sources is reduced by nearly 25,000. The previous version of the catalog does have sources in the overlap regions, but their flux densities are considered unreliable due to calibration errors. The flux densities should be more accurate in this catalog, biases are smaller, and the incidence of spurious sources is also reduced. Over most of the survey area, the detection limit is 1 mJy. A region along the equatorial strip (RA = 21.3 to 3.3 hrs, Dec = -1 to 1 deg) has a deeper detection threshold because two epochs of observation were combined. The typical detection threshold in this region is 0.75 mJy. There are approximately 4,500 sources below the 1 mJy threshold used for most previous versions of the catalog. The format of this catalog is the same as releases since 13Jun05 but differs from earlier versions of the catalog. It contains two parameters which give information on the epoch of observation for each source (called mean_epoch and rms_epoch in this HEASARC version) which are described below. The P(S) parameter (called sidelobe_prob herein), which indicates the probability that the source is a sidelobe, replaces the previous binary sidelobe flag column. The parameters sdss_matches, sdss_first_offset, sdss_imag, sdss_class, twomass_matches, twomass_first_offset and twomass_kmag give information on counterparts to the FIRST source in the SDSS DR10 catalog and the 2MASS catalog, respectively. Other catalog parameters are common with FIRST catalog releases extending back over the past decade. The co-added images are available online: see the FIRST page at <a href="http://sundog.stsci.edu/first/images.html">http://sundog.stsci.edu/first/images.html</a> for details. The source catalog presented here is derived from the images. Data for the FIRST survey were collected in all VLA B-configurations from Spring 1993 through Spring 2004. For all data collected for the FIRST project, the raw u-v visibility data are placed in the VLA public archive on the day they are taken, and are available for use without restriction. Additional data in the southern Galactic cap were acquired in Spring 2009 and Spring 2011. The VLA was in a hybrid condition in 2009, with some new EVLA receivers and some old VLA receivers. The characteristics of those images are slightly different from the older data, but for most purposes they should be equivalent. In 2011 the EVLA receivers were available with an early version of the new EVLA data system, so there are a number of differences from the old data: <pre> Date Frequencies Bandpass Integration Before 2011 1365, 1435 MHz 2x7 3-MHz channels 180 seconds 2011 1335, 1730 MHz 2x64 2-MHz channels 60 seconds </pre> Note particularly the frequency difference between the new and older data. The new data are in co-added fields with names ending with 'S' (and later letters in the alphabet) and are found entirely in the south Galactic cap. This table was last updated by the HEASARC in May 2015 based on the file: <a href="http://sundog.stsci.edu/first/catalogs/catalog_14dec17.bin.gz">http://sundog.stsci.edu/first/catalogs/catalog_14dec17.bin.gz</a> which contains the 17 December 2014 version of the FIRST Source Catalog. Some of the values for the name parameter in the HEASARC's implementation of this table were corrected in April 2018. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/friicat
- Title:
- FIRST Catalog of FR II Radio Galaxies
- Short Name:
- FRIICAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of 123 Fanaroff and Riley class II edge-brightened radio galaxies (FR IIs), called FRIICAT, that has been selected from a published sample obtained by combining observations from the NVSS, FIRST, and SDSS surveys. The catalog includes sources with redshift <=0.15, an edge-brightened radio morphology, and those with at least one of the emission peaks located at a radius r larger than 30 kpc from the center of the host. The radio luminosity at 1.4 GHz of the FRIICAT sources covers the range L<sub>1.4</sub> ~ 10<sup>39.5</sup> - 10<sup>42.5</sup> erg/s. The FRIICAT catalog has 90% of low- and 10% of high-excitation galaxies (LEGs and HEGs), respectively. The properties of these two classes are significantly different. The FRIICAT LEGs are mostly luminous (-20 >~ M<sub>r</sub> >~ -24), red early-type galaxies with black hole masses in the range 10<sup>8</sup> M<sub>sun</sub> <~ M<sub>BH</sub> <~ 10<sup>9</sup> M_sun_; they are essentially indistinguishable from the FR Is belonging to the FRICAT sample (Capetti et al. 2017, A&A, 598, A49: also available as a HEASARC table). The HEG FR IIs are associated with optically bluer and mid-IR redder hosts than the LEG FR IIs and to galaxies and black holes that are smaller, on average, by a factor of ~2. FR IIs have a factor of ~3 higher average radio luminosity than FR Is. Nonetheless, most (~90%) of the selected FR IIs have a radio power that is lower, by as much as a factor of ~100, than the transition value between FR Is and FR IIs found in the 3C sample. The correspondence between the morphological classification of FR I and FR II and the separation in radio power disappears when including sources selected at low radio flux thresholds, which is in line with previous results. In conclusion, a radio source produced by a low-power jet can be edge brightened or edge darkened, and the outcome is not related to differences in the optical properties of the host galaxy. The authors searched for FR II radio galaxies in the sample of 18,286 radio sources built by Best & Heckman (2012, MNRAS, 421, 1569) by limiting their search to the subsample of objects in which, according to these latter authors, the radio emission is produced by an active nucleus. They cross-matched the optical spectroscopic catalogs produced by the group from the Max Planck Institute for Astrophysics and Johns Hopkins University (Brinchmann et al. 2004, MNRAS, 351, 1151; Tremonti et al. 2004, ApJ, 613, 898) based on data from the Data Release 7 of the Sloan Digital Sky Survey (DR7/SDSS; Abazajian et al. 2009, ApJS, 182, 543) with the National Radio Astronomy Observatory Very Large Array Sky Survey (NVSS; Condon et al. 1998, AJ, 115, 1693, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/65">CDS Cat. VIII/65</a>) and the Faint Images of the Radio Sky at Twenty centimeters survey (FIRST; Becker et al. 1995, ApJ, 450, 559; Helfand et al. 2015, ApJ, 801, 26, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/92">CDS Cat. VIII/92</a>) adopting a radio flux density limit of 5 mJy in the NVSS. The authors focused on those sources with redshift z < 0.15. The majority (108) of the selected FR IIs are classified as LEG, but there are also 14 HEG and just one source that cannot be classified spectroscopically because of the lack of emission lines, namely SDSS J144625.13+214209.8. Throughout this study, the authors adopted a cosmology with H<sub>0</sub> = 67.8 km s<sup>-1</sup> Mpc<sup>-1</sup>, Omega<sub>M</sub> = 0.308, and Omega<sub>Lambda</sub> = 0.692 (Planck Collaboration XIII 2016, A&A, 594, A13). This table was created by the HEASARC in May 2017 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/601/A81">CDS Catalog J/A+A/601/A81</a> file table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/fricat
- Title:
- FIRST Catalog of FR I Radio Galaxies
- Short Name:
- FRICAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have built a catalog of 219 Fanaroff and Riley class I edge-darkened radio galaxies (FR Is), called FRICAT, that is selected from a published sample and obtained by combining observations from the NVSS, FIRST, and SDSS surveys. They included in the catalog the sources with an edge-darkened radio morphology, redshift <= 0.15, and extending (at the sensitivity of the FIRST images) to a radius r larger than 30 kpc from the center of the host. The authors also selected an additional sample (sFRICAT) of 14 smaller (10 < r < 30 kpc) FR Is, limiting to z < 0.05. The hosts of the FRICAT sources are all luminous (-21 >~ M<sub>r</sub> >~ 24), red early-type galaxies with black hole masses in the range 10<sup>8</sup> <~ M<sub>BH</sub> <~ 3 x 10<sup>9</sup> solar masses); the spectroscopic classification based on the optical emission line ratios indicates that they are all low excitation galaxies. Sources in the FRICAT are then indistinguishable from the FR Is belonging to the Third Cambridge Catalogue of Radio Sources (3C) on the basis of their optical properties. Conversely, while the 3C-FR Is show a strong positive trend between radio and [O III] emission line luminosity, these two quantities are unrelated in the FRICAT sources; at a given line luminosity, they show radio luminosities spanning about two orders of magnitude and extending to much lower ratios between radio and line power than 3C-FR Is. The authors' main conclusion is that the 3C-FR Is represent just the tip of the iceberg of a much larger and diverse population of FR Is. This HEASARC table contains both the 219 radio galaxies in the main FRICAT sample listed in Table B.1 of the reference paper and the 14 radio galaxies in the additional sFRICAT sample listed in Table B.2 of the reference paper. To enable users to distinguish from which sample an entry has been taken, the HEASARC created a parameter galaxy_sample which is set to 'M' for galaxies from the main sample, and to 'S' for galaxies from the supplementary sFRICAT sample. Throughout the paper, the authors adopted a cosmology with H<sub>0</sub> = 67.8 km s<sup>-1</sup> Mpc<sup>-1</sup>, Omega<sub>M</sub> = 0.308, and Omega<sub>Lambda</sub> = 0.692 (Planck Collaboration XIII 2016). This table was created by the HEASARC in February 2017 based on electronic versions of Tables B.1 and B.2 that were obtained from the Astronomy & Astrophysics website. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gpa
- Title:
- First Galactic Plane Survey at 8.35 and 14.35 GHz
- Short Name:
- GP8.35/14.35
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from the first Galactic Plane (GP) Survey at 8.35 and 14.35 GHz (3.6 and 2.1 cm). In this project, the first images of the GP in the galactic latitude range |b| < 5 degrees and the galactic longitude range -15 degrees < l < 255 degrees at 8.35 and 14.35 GHz were presented. These observations used the National Radio Astronomy Observatory-NASA Green Bank Earth Station to survey the sky simultaneously at these two frequencies. These GPA data are the first results from the GP Survey observations, a program to monitor this portion of the sky at 8.35 and 14.35 GHz. The GP Survey series is intended to detect short-lived radio sources. In their published paper, the authors presented four independent observations of the Galactic plane, combined to provide a set of reference images of the Galactic plane. This first GPA survey covers 0.82 steradian (6.5%) of the sky. This table conatins a source list of all sources which were brighter than 0.9 Jy at 8.35 GHz and also of all sources brighter than 2.5 Jy at 14.35 GHz. The FITS format images, residual images, source lists, and archive data are available over the internet at <a href="http://www.gb.nrao.edu/~glangsto/GPA">http://www.gb.nrao.edu/~glangsto/GPA</a> . This table was created by the HEASARC in December 2004 based on CDS catalog J/AJ/119/2801/, tables s8.dat and s14.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gleamegcat
- Title:
- GaLactic and Extragalactic All-sky MWA Survey (GLEAM) Extragalactic Catalog
- Short Name:
- GLEAMEGCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Using the Murchison Widefield Array (MWA), the low-frequency Square Kilometre Array (SKA1 LOW) precursor located in Western Australia, the authors have completed the GaLactic and Extragalactic All-sky MWA (GLEAM) survey, and present the resulting extragalactic catalog, utilizing the first year of observations. The catalog covers 24,402 square degrees, over Declinations south of +30 degrees and Galactic latitudes outside 10 degrees of the Galactic Plane, excluding some areas such as the Magellanic Clouds. It contains 307,455 radio sources with 20 separate flux density measurements across 72 - 231 MHz, selected from a time- and frequency-integrated image centered at 200 MHz, with a resolution of ~ 2 arcminutes. Over the catalogued region, the authors estimate that the catalog is 90% complete at 170 mJy, and 50% complete at 55 mJy, and large areas are complete at even lower flux density levels. Its reliability is 99.97% above the 5-sigma detection threshold, which itself is typically 50 mJy. These observations constitute the widest fractional bandwidth and largest sky area survey at radio frequencies to date, and calibrate the low frequency flux density scale of the southern sky to better than 10%. The reference paper presents details of the flagging, imaging, mosaicking, and source extraction/characterization, as well as estimates of the completeness and reliability. All source measurements and images are available online at <a href="http://www.mwatelescope.org/">http://www.mwatelescope.org/</a>. This is the first in a series of publications describing the GLEAM survey results. GLEAM observes in week-long drift scan campaigns, with a single Dec strip observed each night. The observing bandwidth of 72-231 MHz is covered by shifting frequencies by 30.72 MHz every two minutes, avoiding the Orbcomm satellite constellation at 134-139 MHz. Thus, the frequencies of observation are 72-103, 103-134, 139-170, 170-200. and 200-231 MHz. These may be further subdivided for imaging purposes; in this study, the 30.72 MHz bandwidth is commonly subdivided into four 7.68 MHz sub-channels. The native channel resolution of these observations is 40 kHz and the native time resolution is 0.5 seconds. This paper concerns only data collected in the first year, i.e. four weeks between June 2013 and July 2014. The authors also do not image every observation, since the survey is redundant across approximately 50% of the observed RA ranges, and some parts are adversely acted by the Galactic plane and Centaurus A. Table 1 in the reference paper lists the observations which have been used to create this first GLEAM catalog. The HEASARC has converted the flux density units from those given in the original table (Jy and Jy/beam) to its standard units for radio flux densities (mJy and mJy/beam). This table was originally ingest by the HEASARC in February 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/100">CDS Catalog VIII/100</a> file gleamegc.dat, the GLEAM Extragalactic Catalog. It was updated in May 2018 to the corrected version provided to the CDS by the author. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gcps
- Title:
- Galactic Center P-Band (330 MHz) Survey
- Short Name:
- GCPS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Galactic Center P-Band (330 MHz) Survey (GCPS) is based on wide-field, subarcminute-resolution Very Large Array (VLA) imagery of the Galactic center region at 330 MHz. With a resolution of ~7"x12" and an rms noise of 1.6 mJy/beam, this image represented a significant increase in resolution and sensitivity over the previously published VLA image at this frequency. The improved sensitivity more than tripled the census of small-diameter sources in the region, resulted in the detection of two new nonthermal filaments (NTFs), 18 NTF candidates, and 30 pulsar candidates, revealed previously known extended sources in greater detail, and has resulted in the first detection of Sagittarius A* in this frequency range. Two sets of observations were obtained. The first was conducted at 330 MHz in the A configuration of the VLA in 1996 October. The second set of P-band observations were obtained in the A and B configurations of the VLA between 1998 March and 1999 May. This Browse table was created by the HEASARC in May 2005 based on the CDS Catalog J/AJ/128/1646, tables table2.dat and table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtas150m
- Title:
- Giant Metrewave Radio Telescope All-Sky 150-MHz Radio Source Catalog
- Short Name:
- GMRTAS150M
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from the first full release of a survey of the 150-MHz radio sky, observed with the Giant Metrewave Radio Telescope (GMRT) between April 2010 and March 2012 as part of the TIFR GMRT Sky Survey (TGSS) project. Aimed at producing a reliable compact source survey, the authors' automated data-reduction pipeline efficiently processed more than 2000 hours of observations with minimal human interaction. Through application of innovative techniques such as image-based flagging, direction-dependent calibration of ionospheric phase errors, correcting for systematic offsets in antenna pointing, and improving the primary beam model, the authors created good quality images for over 95% of the 5,336 pointings. This data release covers 36,900 deg<sup>2</sup> (or 3.6 pi steradians) of the sky between -53 and +90 degrees Declination, which is 90% of the total sky. The majority of pointing images has a noise level below 5 mJy/beam (the median RMS background noise is 3.5 mJy per beam), with an approximate resolution of 25" x 25" (or 25" x 25"/cos(Dec-19<sup>o</sup>) for pointings south of 19 degrees Declination). The authors have produced a catalog of 0.62 Million radio sources with flux densities ranging from 11.1 mJy to 9.22 kJy that are derived from an initial, high-reliability source extraction at the 7-sigma level. For the bulk of the survey, the measured overall astrometric accuracy is better than 2 arcseconds in Right Ascension and Declination, while the flux density accuracy is estimated at approximately 10%. Within the scope of the TGSS Alternative Data Release (TGSS ADR) project, the source catalog, as well as 5,336 mosaic images (5 x 5 degree<sup>2</sup>) and an image cutout service, are made publicly available as a service to the astronomical community. (The TGSS images and cutout server are available through the project website at <a href="http://tgssadr.strw.leidenuniv.nl/">http://tgssadr.strw.leidenuniv.nl/</a>). In addition to enabling a wide range of different scientific investigations, the authors anticipate that these survey products will provide a solid reference for various new low-frequency radio aperture array telescopes (LOFAR, LWA, MWA, SKA-low), and can play an important role in characterizing the epoch-of-reionization (EoR) foreground. The TGSS ADR project aims at continuously improving the quality of the survey data products. Near-future improvements include replacement of bright source snapshot images with archival targeted observations, using new observations to fill the holes in sky coverage and to replace very poor quality observational data, and an improved flux calibration strategy for less severely affected observational data. This table was created by the HEASARC in February 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/598/A78">CDS Catalog J/A+A/598/A78</a> file table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtelain1
- Title:
- Giant Metrewave Radio Telescope ELAIS-N1 Field 610-MHz Radio Source Catalog
- Short Name:
- GMRTELAIN1
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a source catalog based on observations of the European Large-Area ISO Survey-North 1 (ELAIS-N1) field taken at 610 MHz with the Giant Metrewave Radio Telescope. Nineteen pointings were observed, covering a total area of ~ 9 square degrees with a resolution of 6 x 5 arcsec<sup>2</sup>, position angle of +45 degrees. Four of the pointings were deep observations with an rms of ~ 40 microJansky (uJy) before primary beam correction, with the remaining fifteen pointings having an rms of ~ 70 uJy. The techniques used for data reduction and production of a mosaicked image of the region are described in the reference paper, where the final mosaic, along with a catalog of 2500 sources detected above a 6-sigma threshold, are presented. This work complements the large amount of optical and infrared data already available on the region. In their paper, the authors calculate 610-MHz source counts down to 270 uJy, and find further evidence for the turnover in differential number counts below 1 mJy, previously seen at both 610 MHz and 1.4 GHz. For further details of the surveys and data analysis procedures, please refer to the published paper. This table contains the ELAIS-N1 catalog of 2500 detected 610-MHz radio sources. This table was created by the HEASARC in February 2012 based on CDS Catalog J/MNRAS/383/75 file catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtelain2
- Title:
- Giant Metrewave Radio Telescope ELAIS-N2 Field 610-MHz Radio Source Catalog
- Short Name:
- GMRTELAIN2
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a source catalog based on observations of the European Large-Area ISO Survey-North 2 (ELAIS-N2) field taken at 610 MHz with the Giant Metrewave Radio Telescope (GMRT). Thirteen pointings were observed, covering a total area of ~ 6 square degrees with a resolution of 6.5 x 5 arcsec<sup>2</sup>, position angle of +70 degrees. The rms noise at the center of the pointings is typically ~ 85 microJansky (uJy) before correction for the GMRT primary beam . The techniques used for data reduction and production of a mosaicked image of the region are described in the reference paper, where the final mosaic, along with a catalog of 1310 sources detected above a 6-sigma threshold, are presented. The survey complements existing radio and infrared data that are available for this region. For further details of the surveys and data analysis procedures, please refer to the published paper. This table contains the ELAIS-N2 catalog of 1310 detected 610-MHz radio sources. This table was created by the HEASARC in February 2012 based the source catalog of the Cambridge GMRT Survey of the ELAIS-N2 region which was obtained from the University of Cambridge Astrophysics Group Surveys and Catalogs website at <a href="http://www.mrao.cam.ac.uk/facilities/surveys/gmrt/elais-n2/">http://www.mrao.cam.ac.uk/facilities/surveys/gmrt/elais-n2/</a> file GMRT_EN2_dr1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrt4f150m
- Title:
- Giant Metrewave Radio Telescope Field I 150-MHz Radio Source Catalog
- Short Name:
- GMRT4F150M
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Foreground removal is a major challenge for detecting the redshifted 21-cm neutral hydrogen (HI) signal from the Epoch of Reionization. The authors have used 150-MHz Giant Metrewave Radio Telescope (GMRT) observations to characterize the statistical properties of the foregrounds in four different fields of view. The observational data were used to assess point source subtraction. Considering the brightest source (~1 Jy) in each field, the authors find that the residual artefacts are less than 1.5% in the most sensitive field (FIELD I). Considering all the sources in the fields, they find that the bulk of the image is free of artefacts, the artefacts being localized to the vicinity of the brightest sources. The authors have used FIELD I, which has an rms noise of 1.3 mJy beam<sup>-1</sup>, to study the properties of the radio source population to a limiting flux of 9 mJy. The differential source count is well fitted with a single power law of slope -1.6. They find there is no evidence for flattening of the source counts towards lower flux densities which suggests that source population is dominated by the classical radio-loud active galactic nuclei. The authors have observed FIELD I in GMRT Time Allocation Committee (GTAC) cycle 15 in 2008 January, whereas FIELD II and FIELD III were observed in cycle 17 during 2010 February. These target fields were selected at high Galactic latitudes (b > 10<sup>o</sup>) which were up at night time during the GTAC cycles 15 and 17, and which contain relatively few bright sources (>= 0.3 Jy) in the 1400 MHz NRAO VLA Sky Survey (NVSS). Finally, FIELD IV was observed in cycle 8 (2005 June). Full details of these 4 observations are given in Table 1 of the reference paper. This table contains the 150-MHz source catalog for the most sensitive observation, namely the 9.8-hour observation of Field I (centered on J2000.0 RA and Dec of 5<sup>h</sup> 30<sup>m</sup> 00<sup>s</sup>, +60<sup>o</sup> 00' 00"), which was made on 2008 January 8. This table was created by the HEASARC in September 2013 based on CDS Catalog J/MNRAS/426/3295 file tablea1.dat This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtha325m
- Title:
- Giant Metrewave Radio Telescope Herschel-ATLAS/GAMA Flds 325-MHz Source Catalog
- Short Name:
- GMRTHA325M
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a source list from a 325-MHz survey undertaken with the Giant Metrewave Radio Telescope (GMRT). This survey covers a large part of the three equatorial fields at 9, 12 and 14.5 h of Right Ascension from the Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS) in the area also covered by the Galaxy And Mass Assembly (GAMA) survey. The full data set, after some observed pointings were removed during the data reduction process, comprises 212 GMRT pointings covering ~90 deg<sup>2</sup> of sky. A list of the central coordinates of the images from which the sources listed in this catalog are derived is available at <a href="http://gmrt-gama.extragalactic.info/GMRT_GAMA_IMAGE_CENTERS">http://gmrt-gama.extragalactic.info/GMRT_GAMA_IMAGE_CENTERS</a>. The images themselves are available at <a href="http://gmrt-gama.extragalactic.info/">http://gmrt-gama.extragalactic.info/</a>. The authors have imaged and catalogued the data using a pipeline that automates the process of flagging, calibration, self-calibration and source detection for each of the survey pointings. The resulting images have resolutions of between 14 and 24 arcseconds and minimum rms noise (away from bright sources) of ~1 mJy beam<sup>-1</sup>, and the catalogue contains 5263 sources brighter than the local 5 sigma values. In the reference paper, the authors investigate the spectral indices of those GMRT sources which are also detected at 1.4 GHz and find them to agree broadly with previously published results; there is no evidence for any flattening of the radio spectral index below S<sub>1.4</sub> = 10 mJy. This work adds to the large amount of available optical and infrared data in the H-ATLAS equatorial fields and will facilitate further study of the low-frequency radio properties of star formation and AGN activity in galaxies out to z ~1. This table was created by the HEASARC in December 2013 based on electronic versions of the 3 catalogs that comprise Table 3 from the reference paper which were 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/gmrt1hxcsf
- Title:
- Giant Metrewave Radio Telescope 1h XMM/Chandra Survey Fld 610-MHz Source Catalog
- Short Name:
- GMRT1HXCSF
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the results of a deep 610-MHz survey of the 1<sup>hr</sup> 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 microJy (uJy). 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 1<sup>hr</sup> field (centered at (J2000.0) RA, Dec = 01<sup>h</sup> 45<sup>m</sup> 27<sup>s</sup>, -04<sup>o</sup> 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 .
- ID:
- ivo://nasa.heasarc/gmrtj0916
- Title:
- Giant Metrewave Radio Telescope J0916+6348 Field Radio Source Catalog
- Short Name:
- GMRTJ0916
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog based on deep multifrequency observations made using the Giant Metrewave Radio Telescope (GMRT) at 153, 244, 610 and 1260 MHz of a field centred on J0916+6348, to search for evidence of fossil radio lobes which could be due to an earlier cycle of episodic activity of the parent galaxy, as well as haloes and relics in clusters of galaxies. The authors do not find any unambiguous evidence of episodic activity in a list of 374 sources, suggesting that such activity is rare even in relatively deep low-frequency observations. The authors examine the spectra of all the sources by combining their observations with those from the Westerbork Northern Sky Survey (WENSS), NRAO (National Radio Astronomy Observatories) VLA (Very Large Array) Sky Survey (NVSS) and the Faint Images of the Radio Sky at Twenty-Centimeters Survey (FIRST). Considering only those which have measurements at a minimum of 3 different frequencies, they find that almost all sources are consistent with a straight spectrum with a median spectral index alpha ~ 0.8 (S<sub>nu</sub> ~ nu<sup>-alpha</sup>) which appears steeper than theoretical expectations of the injection spectral index. The authors identify 14 very-steep-spectrum sources with alpha >~ 1.3. This table contains the list of 317 sources (out of the 374 sources which were within 1.5 degrees of the phase center at 153 MHz and had peak brightnesses at least 6 times larger than the local rms value) which were detected at a minimum of 3 frequencies out of the 6 frequencies (153, 244, 327, 610, 1260 and 1400 MHz) which were utilized in this study. The new observations were made on 2005 December 12 at 153 MHz, 2005 November 26 at 244 MHz and 610 MHz, and on 2008 April 22 at 1260 MHz, on the Giant Metrewave Radio Telescope (Pune, India). This table was created by the HEASARC in March 2012 based on CDS Catalog J/MNRAS/392/1403 file table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtlbdsly
- Title:
- Giant Metrewave Radio Telescope LBDS-Lynx Region 150-MHz Radio Source Catalog
- Short Name:
- GMRTLBDSLY
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- It has been known for nearly three decades that high-redshift radio galaxies exhibit steep radio spectra, and hence ultrasteep spectrum radio sources provide candidates for high-redshift radio galaxies. Nearly all radio galaxies with z > 3 have been found using this redshift-spectral index correlation. The authors have started a program with the Giant Metrewave Radio Telescope (GMRT) to exploit this correlation at flux density levels about 10 to 100 times deeper than the known high-redshift radio galaxies which were identified primarily using the already available radio catalogs. In their program, they have obtained deep, high-resolution radio observations at 150 MHz with the GMRT for several "deep" fields which are well studied at higher radio frequencies and in other bands of the electromagnetic spectrum, with the aim to detect candidate high-redshift radio galaxies. In their paper, they present results from the deep 150-MHz observations of the LBDS (Leiden-Berkeley Deep Survey) Lynx field, which has been already imaged at 327, 610 and 1412 MHz with the Westerbork Synthesis Radio Telescope (WSRT) and at 1400 and 4860 MHz with the Very Large Array (VLA). The counterparts for the 150-MHz sources at higher radio frequencies were searched within a 20-arcsec radius from the 150-MHz position. The 150-MHz image made with the GMRT has an rms noise of ~ 0.7 mJy beam<sup>-1</sup> and a resolution of ~ 19 x 15 arcsec<sup>2</sup>. It is the deepest low-frequency image of the LBDS-Lynx field. The source catalog of this field at 150 MHz has 765 sources down to ~ 20% of the primary beam response, covering an area of about 15 deg<sup>2</sup>. The spectral index was estimated by cross-correlating each source detected at 150 MHz with the available observations at 327, 610, 1400 and 4860 MHz and also using available radio surveys such as the Westerbork Northern Sky Survey (WENSS) at 327 MHz and the NRAO VLA Sky Survey (NVSS) and the Faint Images of the Radio Sky at Twenty-cm (FIRST) survey at 1400 MHz. A total of 639 sources out of 765 (83%) have spectral indices determined. The remaining 17% of the sources are mostly weak radio sources with a median flux density of ~ 9 mJy, or fall in the regions where deep observations at higher frequencies do not exist. The median spectral index of the sample is 0.78. The authors find about 150 radio sources with spectra steeper than 1. About two-thirds of these are not detected in the Sloan Digital Sky Survey (SDSS), hence are strong candidate high-redshift radio galaxies, which need to be further explored with deep infrared imaging and spectroscopy to estimate the redshift. The list of the 98 such steep-spectrum sources lacking SDSS counterparts is given in Table 4 of the published paper. This table was created by the HEASARC in February 2012 based on CDS Catalog J/MNRAS/405/436 file table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtlhcat
- Title:
- Giant Metrewave Radio Telescope Lockman Hole 610-MHz Radio Source Catalog
- Short Name:
- GMRTLHCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a source catalog based on observations of the Lockman Hole with the Giant Metrewave Radio Telescope (GMRT) taken at 610 MHz (49 cm). Twelve pointings were observed, covering a total area of ~5 deg<sup>2</sup> with a resolution of 6 x 5 arcsec<sup>2</sup>, position angle +45 degrees. The majority of the pointings have an rms noise of ~ 60 microJy/beam (uJy/beam) before correction for the attenuation of the GMRT primary beam. The techniques used for data reduction and the production of a mosaicked image of the region are described in the reference paper, where the final mosaic is presented, along with a catalog of 2845 sources detected above the 6-sigma threshold which is contained in this table. In the paper, radio source counts are calculated at 610 MHz and combined with existing 1.4-GHz source counts, in order to show that pure luminosity evolution of the local radio luminosity functions for active galactic nuclei and starburst galaxies is sufficient to account for the two source counts simultaneously. The 'central region' of the Lockman Hole, consisting of 12 pointings spaced by 36 arcminutes in a hexagonal pattern (shown in Fig. 1 of the reference paper) was observed on 2004 July 24 and 25 using the GMRT. The observations were made in two 16-MHz sidebands centered on 610 MHz, each split into 128 spectral channels, with a 16.9s integration time. This table was created by the HEASARC in February 2012 based on CDS Catalog J/MNRAS/387/1037 file catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtlhcat2
- Title:
- Giant Metrewave Radio Telescope Lockman Hole 610-MHz Radio Source Catalog 2
- Short Name:
- GMRTLHCAT2
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a source catalog based on further observations of the Lockman Hole field, made with the Giant Metrewave Radio Telescope at 610 MHz with an angular resolution of 6 x 5 arcsec<sup>2</sup>. These complement this group's earlier observations of the central ~ 5 deg<sup>2</sup> of the Lockman Hole (Garn et al. 2008, MNRAS, 387, 1037, the HEASARC Browse table GMRTLHCAT) by covering a further ~ 8 deg<sup>2</sup> area, with an rms noise down to ~ 80 microJansky/beam (uJy/beam). A catalog of 4934 radio sources in both the inner and outer regions of the Lockman Hole is presented in this table. The earlier survey had 12 pointings covering ~ 5 square degrees in the center of the Lockman Hole, and herein a further 26 pointings in the outer parts of the Lockman Hole are added, to cover a total of ~ 14 square degrees. To match the earlier survey, the images were made with a resolution of 6" x 5", at a position angle of +45 degrees. The majority of the new pointings have an rms noise of ~80 uJy/beam before the primary beam correction, but the noise in the west - particularly near the very bright source 3C244.1 - is worse. This table was created by the HEASARC in February 2012 based on CDS Catalog J/BASI/38.103 file gmrtlh2.cat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtlhcat3
- Title:
- Giant Metrewave Radio Telescope Lockman Hole 610-MHz Radio Source Catalog 3
- Short Name:
- GMRTLHCAT3
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- In the run-up to routine observations with the upcoming generation of radio facilities, the nature of the sub-mJy radio population has been hotly debated. In this paper, the authors describe multi-frequency data designed to probe the emission mechanism that dominates in these faint radio sources. Their analysis is based on observations of the Lockman Hole (LH) using the Giant Metrewave Radio Telescope (GMRT) near Pune, India - the deepest 610-MHz imaging yet reported - together with 1.4-GHz imaging from the Very Large Array (VLA), which are well matched in resolution and sensitivity to the GMRT data: sigma<sub>610MHz</sub> ~ 15 microJy/beam (uJy/beam), sigma}<sub>1.4GHz</sub> ~ 6 uJy/beam, and full width at half-maximum (FWHM) ~ 5 arcseconds. The GMRT and VLA data are cross-matched to obtain the radio spectral indices for the faint radio emitters. During six 12-hr sessions in 2006 February and July, the authors obtained data at 610 MHz for three pointings (FWHM ~ 43 arcminutes) in the LH (see Table 1 of the reference paper for full details), separated by 11 arcminutes (the LOCKMAN-E, LOCK-3 and LHEX-4 fields), typically with 28 of the 30 antennas that comprise the GMRT. The total integration time in each field, after overheads, was 16 hr. The final image had a noise level in the central 100 arcmin<sup>2</sup> of 14.7 uJy/beam, the deepest map reported at 610 MHz as of the date of publication, despite the modest integration time. New and archival data were obtained at the same three positions using the National Radio Astronomy Observatory's VLA, largely in its B configuration. This table contains 1585 sources found in the LH field at 610 MHz by the GMRT. For 19 of the sources which have multiple components, the 34 individual components are listed as well. Thus, the final table contains 1619 (1585 + 34) entries. Source extraction was based on criteria of peak brightness > 5 times the local rms and integrated flux density > 3 times the local rms. This table was created by the HEASARC in February 2012 based on CDS Catalog J/MNRAS/397/281 file table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtk2f1lf
- Title:
- Giant Metrewave Radio Telescope 150-MHz Survey of Kepler K2 Field 1
- Short Name:
- GMRTK2F1LF
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results from the first dedicated radio continuum survey of a Kepler K2 mission field, Field 1, covering the North Galactic Cap. The survey was wide-field, contemporaneous, multi-epoch, and multi-resolution in nature and was conducted at low radio frequencies between 140 and 200 MHz. The multi-epoch and ultra-wide-field (but relatively low-resolution) part of the survey was provided by 15 nights of observation using the Murchison Widefield Array (MWA) over a period of approximately a month, contemporaneous with K2 observations of this field. The multi-resolution aspect of the survey was provided by the low-resolution (4 arcminutes) MWA imaging, complemented by non-contemporaneous but much higher resolution (20 arcseconds) observations using the Giant Metrewave Radio Telescope (GMRT). The survey is, therefore, sensitive to the details of radio structures across a wide range of angular scales. Consistent with other recent low radio frequency surveys, no significant radio transients or variables were detected in the survey. The resulting source catalogs consist of 1,085 and 1,468 detections in the two MWA observation bands (centered at 154 and 185 MHz, respectively) and 7,445 detections in the GMRT observation band (centered at 148 MHz), over 314 square degrees. The survey is presented as a significant resource for multi-wavelength investigations of the more than 21,000 target objects in the K2 field. In the reference paper, the authors briefly examined their survey data against K2 target lists for dwarf star types (stellar types M and L) that had been known to produce radio flares. This survey included contemporaneous observations of the K2 Field 1 made with the MWA and historical (from 2010-2012) observations made with the Tata Institute of Fundamental Research (TIFR) GMRT Sky Survey (TGSS; see <a href="http://tgss.ncra.tifr.res.in/">http://tgss.ncra.tifr.res.in/</a>), via the TGSS Alternative Data Release 1 (ADR1; Intema et al. 2016, in prep.). The MWA and GMRT are radio telescopes operating at low radio frequencies (approximately 140-200 MHz for the work described here). The K2 mission Campaign 1 was conducted on Field 1 (center at J2000.0 coordinates RA of 11:35:45.51 and Dec of +01:25:02.28;), covering the North Galactic Cap, between 2014 May 30 and August 21. A full survey of the radio sky at 150 MHz as visible from the GMRT was performed within the scope of the PI-driven TGSS project between 2010 and early 2012, covering the declination range from -55 to +90 degrees. Summarizing the observational parameters as given on the TGSS project website (<a href="http://tgss.ncra.tifr.res.in/150MHz/obsstrategy.html">http://tgss.ncra.tifr.res.in/150MHz/obsstrategy.html</a>), the survey consists of more than 5,000 pointings on an approximate hexagonal grid. Data were recorded in full polarization (RR, LL, RL, LR) every 2 seconds, in 256 frequency channels across 16 MHz of bandwidth (140-156 MHz). Each pointing was observed for about 15 minutes, split over three or more scans spaced in time to improve UV-coverage. Typically, 20-40 pointings were grouped together into single night-time observing sessions, bracketed and interleaved by primary (flux density and bandpass) calibrator scans on 3C48, 3C147, and/or 3C286. Interleaving secondary (phase) calibrator scans on a variety of standard phase calibrators were also included, but were typically too faint to be of significant benefit at these frequencies. The single epoch TGSS image was processed in the same way as each of the MWA images using the background and noise characterization source finding techniques outlined in Section 3.1.3 of the reference paper. A source catalog was produced from the single TGSS image. For the high-resolution TGSS images, the sources were resolved in some cases and so morphology information is included in this catalog. The final set of MWA images after source finding yielded a total of 1,085 radio sources at 154 MHz, and 1,471 sources at 185 MHz over 314 square degrees, at an angular resolutions of ~4 arcminutes: this MWA catalog is contained in the HEASARC table <a href="/W3Browse/radio-catalog/mwak2f1lfc.html">MWAK2F1HFC</a>, which thus has 1,085 + 1,471 = 2,556 entries. The GMRT images, after source finding, yielded a total of 7,445 radio sources over the same field, at an angular resolution of ~0.3 arcminutes: this GMRT source catalog is contained in the present HEASARC table. Thus, the overall survey covers multiple epochs of observation, spans approximately 140-200 MHz, is sensitive to structures on angular scales from arcseconds to degrees, and the MWA part is contemporaneous with the K2 observations of the field over a period of approximately one month. This table was created by the HEASARC in December 2016 based on CDS Catalog J/AJ/152/82 file table3.dat (the GMRT Kepler 2 Field 1 source catalog). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtspxfls
- Title:
- Giant Metrewave Radio Telescope Spitzer xFLS Field 610-MHz Radio Source Catalog
- Short Name:
- GMRTSPXFLS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a source catalog based on observations of the Spitzer extragalactic First Look Survey (xFLS) field taken at 610 MHz with the Giant Metrewave Radio Telescope (GMRT). Seven individual pointings were observed, covering a total area of ~ 4 square degrees with a resolution of 5.8 x 4.7 arcsec<sup>2</sup>, position angle 60 degrees. The rms noise at the center of the pointings is between 27 and 30 microJansky (uJy) before correction for the GMRT primary beam. The techniques used for data reduction and production of a mosaicked image of the region are described in the reference paper, where the final mosaic, along with a catalog of 3944 sources detected above a ~ 5-sigma threshold, are presented. The survey complements existing radio and infrared data available for this region. For further details of the surveys and data analysis procedures, please refer to the published paper. This table contains the xFLS catalog of 3944 610-MHz radio sources detected by the GMRT, the 05-May-2008 (Release 1.1) version provided to the CDS by the co-author Sally Hales (MRAO, Cambridge). In this version, a rounding error in the right ascension and declination positions listed for some sources in the original 10-May-2007 (Release 1.0) version has been corrected. The source IAU designations remain unchanged, having been based on the correctly computed positions throughout. The main purpose in correcting the positions was to eliminate sporadic mismatches between IAU designation and listed position in the first data release. In other respects the effect on the positions is negligible. This table was created by the HEASARC in February 2012 based on CDS catalog J/MNRAS/376/1251 file gmrtfls.dat, the release 1.1 (05-May-2008) version. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtvvdsvl
- Title:
- Giant Metrewave Radio Telescope VVDS-VLA Deep Field 610-MHz Radio Source Catalog
- Short Name:
- GMRTVVDSVL
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the 5-sigma catalog at 610 MHz of the VIMOS VLT Deep Survey-Very Large Array (VVDS-VLA) deep field obtained from Giant Metrewave Radio Telescope (GMRT) observations. The field is located at RA, Dec = 02:26:00, -04:30:00 (J2000) and covers a 1-square degree area. The GMRT observations imaged the whole 1 square degree field with an angular resolution of 6 arcseconds and an average sensitivity of about 50 µJy/beam. The catalog lists 514 radio sources, 17 of which are fitted with multiple components (between 2 and 5). For these multiple sources, each component (A, B, etc.) is listed separately, and the entire source (indicated by the suffix T in the name) is also listed. Thus, there are 557 entries in this table, 43 of which correspond to multiple components. This table was created by the HEASARC in February 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/463/519">CDS Catalog J/A+A/463/519</a> file table.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtxl240m
- Title:
- Giant Metrewave Radio Telescope XMM Large Scale Structure 240-MHz Source Catalog
- Short Name:
- GMRTXL240M
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The low-frequency radio survey of the XMM-Large Scale Structure (XMM-LSS) field centered at RA (J2000) = 2<sup>h</sup>24<sup>m</sup>00<sup>s</sup>, Dec (J2000) = -4<sup>0</sup>09'47" aims to study the connection between the extragalactic radio source populations and their environment as traced by X-ray and optical emission. In their paper, the authors present new radio observations of the XMM-LSS field carried out using the Giant Meterwave Radio Telescope (GMRT) at 240 and 610 MHz. These observations complement the observations presented by Cohen at al. (2003, ApJ, 591, 640; CDS Cat. <J/ApJ/591/640>) and Tasse et al. (2006, A&A, 456, 791; CDS Cat. <J/A+A/456/791>) at 74 and 325 MHz with the Very Large Array (VLA). At 240 and 610 MHz, the authors reach noise levels of ~2.5 and ~0.3 mJy/beam, leading to the detection of 466 and 769 sources over 18.0 and 12.7 degree<sup>2</sup> with resolutions of 14.7 arcseconds and 6.5 arcseconds, respectively. Combining these data with the available source lists at 74 MHz, 325 MHz (Tasse et al., 2006) and 1400MHz (NVSS), the authors built a multifrequency catalog containing 1611 radio sources. They checked for consistency of the astrometry and flux density estimates. They fit a simple synchrotron radiation model to the flux density measurements of the 318 radio sources that were detected in at least 4 bands. While ~26% of them showed signature of spectral ageing, ~6% showed self absorption. This table contains the GMRT 240-MHz source list, comprising 388 single sources and 183 components of multiple sources, for a total of 571 entries. For the multiple sources, each component (A, B, etc.) is listed separately, in order of decreasing brightness. This table was created by the HEASARC in February 2012 based on CS Catalog J/A+A/471/1105 file table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gmrtxl610m
- Title:
- Giant Metrewave Radio Telescope XMM Large Scale Structure 610-MHz Source Catalog
- Short Name:
- GMRTXL610M
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The low-frequency radio survey of the XMM-Large Scale Structure (XMM-LSS) field centered at RA (J2000) = 2<sup>h</sup>24<sup>m</sup>00<sup>s</sup>, Dec (J2000) = -4<sup>0</sup>09'47" aims to study the connection between the extragalactic radio source populations and their environment as traced by X-ray and optical emission. In their paper, the authors present new radio observations of the XMM-LSS field carried out using the Giant Meterwave Radio Telescope (GMRT) at 240 and 610 MHz. These observations complement the observations presented by Cohen at al. (2003, ApJ, 591, 640; CDS Cat. <J/ApJ/591/640>) and Tasse et al. (2006, A&A, 456, 791; CDS Cat. <J/A+A/456/791>) at 74 and 325 MHz with the Very Large Array (VLA). At 240 and 610 MHz, the authors reach noise levels of ~2.5 and ~0.3 mJy/beam, leading to the detection of 466 and 769 sources over 18.0 and 12.7 degree<sup>2</sup> with resolutions of 14.7 arcseconds and 6.5 arcseconds, respectively. Combining these data with the available source lists at 74 MHz, 325 MHz (Tasse et al., 2006) and 1400MHz (NVSS), the authors built a multifrequency catalog containing 1611 radio sources. They checked for consistency of the astrometry and flux density estimates. They fit a simple synchrotron radiation model to the flux density measurements of the 318 radio sources that were detected in at least 4 bands. While ~26% of them showed signature of spectral ageing, ~6% showed self absorption. This table contains the GMRT 610-MHz source list, comprising 592 single sources and 445 components of multiple sources, for a total of 1037 entries. For the multiple sources, each component (A, B, etc.) is listed separately, in order of decreasing brightness. This table was created by the HEASARC in February 2012 based on CS Catalog J/A+A/471/1105 file table4.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gb6
- Title:
- Green Bank 6-cm (GB6) Radio Source Catalog
- Short Name:
- GB6
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the Green Bank 6-cm (GB6) Radio Source Catalog. The Green Bank 4.85 GHz (6-cm wavelength) survey (Condon J.J., Broderick J.J., Seielstad G.A., Douglas K., & Gregory P.C. in 1994AJ....107.1829C) was made with the NRAO seven-beam receiver on the (former) 91m telescope during 1986 November and 1987 October. The final set of sky maps covering the declination band 0 deg < Dec. < +75 deg was constructed with data from both epochs. Its noise and position errors are nearly a factor of 2^(1/2) smaller than in the epoch 1987 maps, from which the 87GB Catalog (CDS Catalog <VIII/14>) of 54,579 sources stronger than S ~ 25mJy was extracted. Therefore, the new maps were used to make the GB6 catalog of 75,162 discrete sources with angular sizes phi <= 10.5 arcmin and flux densities S >= 18mJy. The GB6 weighted differential source counts S^(5/2)n(S) between 18 mJy and 7 Jy agree well with evolutionary models based on independent data. This table was created by the HEASARC in July 2003 based on CDS Catalog <VIII/40>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gbt31ghz
- Title:
- Green Bank Telescope 100-m 31-GHZ Radio Source Catalog
- Short Name:
- GBT31GHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The 100m Robert C. Byrd Green Bank Telescope (GBT) and the 40m Owens Valley Radio Observatory (OVRO) telescope have been used to conduct a 31-GHz survey of 3165 known extragalactic radio sources over 143 deg<sup>2</sup> of the sky. Target sources were selected from the NRAO VLA Sky Survey (NVSS) in fields observed by the Cosmic Background Imager (CBI); most are extragalactic active galactic nuclei (AGNs) with 1.4-GHz flux densities of 3-10 mJy. Using a maximum-likelihood analysis to obtain an unbiased estimate of the distribution of the 1.4 - 31 GHz spectral indices of these sources, the authors find a mean 31 - 1.4 GHz flux ratio of 0.110 +/- 0.003 corresponding to a spectral index alpha = -0.71+/-0.01 (S<sub>nu</sub> ~ nu<sup>alpha</sup>); 9.0% +/- 0.8% of the sources have alpha > -0.5 and 1.2% +/- 0.2% have alpha > 0. By combining this spectral-index distribution with 1.4GHz source counts, the authors predict 31-GHz source counts in the range 1 mJy <S<sub>31</sub> < 4 mJy, N(>S<sub>31</sub>) = (16.7+/-1.7)deg<sup>-2</sup>(S<sub>31</sub>/1mJy)<sup>(-0.80+/-0.07)</sup>. In this study, the authors present a detailed characterization of the impact of the discrete source foreground on arcminute-scale 31-GHz anisotropy measurements based upon two observational campaigns. The first campaign (the results of which are given in the OVRO31GHZ table) was carried out with the OVRO 40m telescope at 31 GHz from 2000 September through 2002 December. The second campaign (the results of which are given in the present table) used the GBT from 2006 February to May. A companion paper (Sievers et al. 2009arXiv0901.4540S) presents the five-year CBI total intensity power spectrum incorporating the results of the point-source measurements discussed here. Reported error bars include a 10% and 5% rms gain uncertainty for GBT and OVRO measurements, respectively. Sources detected at greater than 4 sigma at 31 GHz are flagged (detection_flag = 'Y'); for this calculation, the random gain uncertainty was excluded. In all 3165 sources were observed. The GBT catalog (this table) contains 1490 sources. Of the 2315 useful OVRO observations many of the non-detections (and a few detections) were superceded by more sensitive GBT observations; the OVRO catalog contained in the HEASARC's OVRO31GHZ table therefore contains data on 1675 sources. The detection rate of the OVRO measurements was 11%, and that of the GBT measurements 25%. In all, 18% of the sources were detected at 31 GHz. This table was created by the HEASARC in June 2012 based on CDS Catalpog J/ApJ/704/1433 file table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lofarbf62m
- Title:
- LOFAR Bootes Field 62-MHz Source Catalog
- Short Name:
- LOFARBF62M
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the source list from Low Frequency Array (LOFAR) Low Band observations of the Bootes field at 62 MHz. The images of this field and the 3C 295 field made at 62 MHz reach a noise level of 5 mJy beam<sup>-1</sup>, making them the deepest images ever obtained at this frequency. In total, the authors detect 329 sources in the Bootes 62-MHz field image, covering an area of 19.4 square degrees out to a primary-beam attenuation factor of 0.4. From the observations, the authors derive Euclidean-normalized differential source counts. The 62-MHz source counts agree with previous GMRT 153 MHz and Very Large Array 74 MHz differential source counts, scaling with a spectral index of -0.7. The authors find that a spectral index scaling of -0.5 is required to match up the LOFAR 34 MHz source counts. This result is also in agreement with source counts from the 38 MHz 8C survey, indicating that the average spectral index of radio sources flattens toward lower frequencies. The authors also find evidence for spectral flattening using the individual flux measurements of sources between 34 and 1400 MHz and by calculating the spectral index averaged over the source population. To select ultra-steep spectrum (alpha < -1.1) radio sources that could be associated with massive high-redshift radio galaxies, the authors compute spectral indices between 62 MHz, 153 MHz, and 1.4 GHz for sources in the Bootes field. They cross-correlate these radio sources with optical and infrared catalogs and fit the spectral energy distribution to obtain photometric redshifts. They find that most of these ultra-steep spectrum sources are located in the 0.7 <~ z <~ 2.5 range. The Bootes and 3C 295 fields were simultaneously observed on 2012 April 12 as part of a multi-beam observation with the LOFAR LBA stations. The idea behind the multi-beam setup was to use the 3C 295 observations as a calibrator field to transfer the gain amplitudes to the (target) Bootes field (pointing center of J2000.0 RA and Dec of 14<sup>h</sup> 32<sup>m</sup> 03.0<sup>s</sup>, +34<sup>o</sup> 16' 33"). The total integration time on both fields was 10.25 hr. The observing band for the Bootes field observations was centered at 62 MHz, with a bandwidth of 16 MHz. The synthesized beam for this observation had dimensions of 31 arcseconds x 19 arcseconds. An overview of the observations is given in Table 1 of the reference paper, and an overview of the image characteristics in Table 2 of the reference paper. This table was created by the HEASARC in January 2015 based on some of the contents of the machine-readable version of Table 3 from the reference paper, namely the 329 entries listing sources in the Bootes field detected at 62 MHz. The remaining entries in this table listing the sources detected in the 3C295 field at frequencies of 34, 46 and 62 MHz are available as the HEASARC tables LOF3C29534, LOF3C29546 and LOF3C29562, respectively. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lof3c29534
- Title:
- LOFAR 3C295 Field 34-MHz Source Catalog
- Short Name:
- LOF3C29534
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the source list from Low Frequency Array (LOFAR) Low Band observations of the 3C 295 field at 34 MHz. The image of this field made at 34 MHz reaches a noise level of 12 mJy beam<sup>-1</sup>, making it the deepest image ever obtained at this frequency. In total, the authors detect 392 sources in the 3C 295 34-MHz field image, covering an area of 52.3 square degrees out to a primary-beam attenuation factor of 0.4. From these and simultaneous observations made at other low-band frequencies, the authors derive Euclidean-normalized differential source counts. The 62-MHz source counts agree with previous GMRT 153 MHz and Very Large Array 74 MHz differential source counts, scaling with a spectral index of -0.7. The authors find that a spectral index scaling of -0.5 is required to match up the LOFAR 34 MHz source counts. This result is also in agreement with source counts from the 38 MHz 8C survey, indicating that the average spectral index of radio sources flattens toward lower frequencies. The authors also find evidence for spectral flattening using the individual flux measurements of sources between 34 and 1400 MHz and by calculating the spectral index averaged over the source population. To select ultra-steep spectrum (alpha < -1.1) radio sources that could be associated with massive high-redshift radio galaxies, the authors compute spectral indices between 62 MHz, 153 MHz, and 1.4 GHz for sources in the Bootes field. They cross-correlate these radio sources with optical and infrared catalogs and fit the spectral energy distribution to obtain photometric redshifts. They find that most of these ultra-steep spectrum sources are located in the 0.7 <~ z <~ 2.5 range. The Bootes and 3C 295 fields were simultaneously observed on 2012 April 12 as part of a multi-beam observation with the LOFAR LBA stations. The idea behind the multi-beam setup was to use the 3C 295 observations as a calibrator field to transfer the gain amplitudes to the (target) Bootes field. The pointing center of the 3C 295 field was J2000.0 RA, Dec = 14<sup>h</sup> 11<sup>m</sup> 20.9<sup>s</sup>, +52<sup>o</sup> 13' 55". The total integration time on both fields was 10.25 hr. The '34-MHz' observing band for the 3C 295 field observations was from 30 - 40 MHz, with 21 sub-bands more or less evenly distributed within this frequency range, with a total bandwidth of 4.1 MHz. The synthesized beam for this observation had dimensions of 56 arcseconds x 30 arcseconds. An overview of the observations is given in Table 1 of the reference paper, and an overview of the image characteristics in Table 2 of the reference paper. This table was created by the HEASARC in January 2015 based on some of the contents of the machine-readable version of Table 3 from the reference paper, namely the 392 entries listing sources in the 3C 295 field detected at 34 MHz. The remaining entries in this table listing the sources detected in the Bootes field at a frequency of 62 MHz. and the sources detected in the 3C295 field at frequencies of 46 and 62 MHz, are available as the HEASARC tables LOFARBF62M, LOF3C29546 and LOF3C29562, respectively. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lof3c29546
- Title:
- LOFAR 3C295 Field 46-MHz Source Catalog
- Short Name:
- LOF3C29546
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the source list from Low Frequency Array (LOFAR) Low Band observations of the 3C 295 field at 46 MHz. The image of this field made at 46 MHz reaches a noise level of 8 mJy beam<sup>-1</sup>, making it the deepest image ever obtained at this frequency. In total, the authors detect 367 sources in the 3C 295 46-MHz field image, covering an area of 30.5 square degrees out to a primary-beam attenuation factor of 0.4. From these and simultaneous observations made at other low-band frequencies, the authors derive Euclidean-normalized differential source counts. The 62-MHz source counts agree with previous GMRT 153 MHz and Very Large Array 74 MHz differential source counts, scaling with a spectral index of -0.7. The authors find that a spectral index scaling of -0.5 is required to match up the LOFAR 34 MHz source counts. This result is also in agreement with source counts from the 38 MHz 8C survey, indicating that the average spectral index of radio sources flattens toward lower frequencies. The authors also find evidence for spectral flattening using the individual flux measurements of sources between 34 and 1400 MHz and by calculating the spectral index averaged over the source population. To select ultra-steep spectrum (alpha < -1.1) radio sources that could be associated with massive high-redshift radio galaxies, the authors compute spectral indices between 62 MHz, 153 MHz, and 1.4 GHz for sources in the Bootes field. They cross-correlate these radio sources with optical and infrared catalogs and fit the spectral energy distribution to obtain photometric redshifts. They find that most of these ultra-steep spectrum sources are located in the 0.7 <~ z <~ 2.5 range. The Bootes and 3C 295 fields were simultaneously observed on 2012 April 12 as part of a multi-beam observation with the LOFAR LBA stations. The idea behind the multi-beam setup was to use the 3C 295 observations as a calibrator field to transfer the gain amplitudes to the (target) Bootes field. The pointing center of the 3C 295 field was J2000.0 RA, Dec = 14<sup>h</sup> 11<sup>m</sup> 20.9<sup>s</sup>, +52<sup>o</sup> 13' 55". The total integration time on both fields was 10.25 hr. The '46-MHz' observing band for the 3C 295 field observations was from 40 - 54 MHz, with 25 sub-bands more or less evenly distributed within this frequency range, with a total bandwidth of 4.9 MHz. The synthesized beam for this observation had dimensions of 40 arcseconds x 24 arcseconds. An overview of the observations is given in Table 1 of the reference paper, and an overview of the image characteristics in Table 2 of the reference paper. This table was created by the HEASARC in January 2015 based on some of the contents of the machine-readable version of Table 3 from the reference paper, namely the 367 entries listing sources in the 3C 295 field detected at 46 MHz. The remaining entries in this table listing the sources detected in the Bootes field at a frequency of 62 MHz. and the sources detected in the 3C295 field at frequencies of 34 and 62 MHz, are available as the HEASARC tables LOFARBF62M, LOF3C29534 and LOF3C29562, respectively. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lof3c29562
- Title:
- LOFAR 3C295 Field 62-MHz Source Catalog
- Short Name:
- LOF3C29562
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the source list from Low Frequency Array (LOFAR) Low Band observations of the 3C 295 field at 62 MHz. The images of this field and the Bootes field made at 62 MHz reach a noise level of 5 mJy beam<sup>-1</sup>, making them the deepest images ever obtained at this frequency. In total, the authors detect 329 sources in the 3C 295 62-MHz field image, covering an area of 17.0 square degrees out to a primary-beam attenuation factor of 0.4. From the observations, the authors derive Euclidean-normalized differential source counts. The 62-MHz source counts agree with previous GMRT 153 MHz and Very Large Array 74 MHz differential source counts, scaling with a spectral index of -0.7. The authors find that a spectral index scaling of -0.5 is required to match up the LOFAR 34 MHz source counts. This result is also in agreement with source counts from the 38 MHz 8C survey, indicating that the average spectral index of radio sources flattens toward lower frequencies. The authors also find evidence for spectral flattening using the individual flux measurements of sources between 34 and 1400 MHz and by calculating the spectral index averaged over the source population. To select ultra-steep spectrum (alpha < -1.1) radio sources that could be associated with massive high-redshift radio galaxies, the authors compute spectral indices between 62 MHz, 153 MHz, and 1.4 GHz for sources in the Bootes field. They cross-correlate these radio sources with optical and infrared catalogs and fit the spectral energy distribution to obtain photometric redshifts. They find that most of these ultra-steep spectrum sources are located in the 0.7 <~ z <~ 2.5 range. The Bootes and 3C 295 fields were simultaneously observed on 2012 April 12 as part of a multi-beam observation with the LOFAR LBA stations. The idea behind the multi-beam setup was to use the 3C 295 observations as a calibrator field to transfer the gain amplitudes to the (target) Bootes field. The pointing center of the 3C 295 field was J2000.0 RA, Dec = 14<sup>h</sup> 11<sup>m</sup> 20.9<sup>s</sup>, +52<sup>o</sup> 13' 55". The total integration time on both fields was 10.25 hr. The observing band for the 3C 295 field 62-MHz observations was 54 - 70 MHz, was centered at 62 MHz, with a full coverage bandwidth of 16 MHz. The synthesized beam for this observation had dimensions of 29 arcseconds x 18 arcseconds. An overview of the observations is given in Table 1 of the reference paper, and an overview of the image characteristics in Table 2 of the reference paper. This table was created by the HEASARC in January 2015 based on some of the contents of the machine-readable version of Table 3 from the reference paper, namely the 329 entries listing sources in the 3C 295 field detected at 62 MHz. The remaining entries in this table listing the sources detected in the Bootes field at a frequency of 62 MHz. and the sources detected in the 3C295 field at frequencies of 34 and 46 MHz, are available as the HEASARC tables LOFARBF62M, LOF3C29534 and LOF3C29546, respectively. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lotssprcat
- Title:
- LOFAR 2-Meter Sky Survey Preliminary Data Release Source Catalog
- Short Name:
- LOTSSPRCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Low Frequency Array (LOFAR) Two-metre Sky Survey (LoTSS) is a deep 120-168 MHz imaging survey that will eventually cover the entire Northern sky. Each of the 3,170 pointings will be observed for 8 hours, which, at most declinations, is sufficient to produce ~5-arcsec resolution images with a sensitivity of ~0.1 mJy/beam and accomplish the main scientific aims of the survey which are to explore the formation and evolution of massive black holes, galaxies, clusters of galaxies and large-scale structure. Due to the compact core and long baselines of LOFAR, the images provide excellent sensitivity to both highly extended and compact emission. For legacy value, the data are archived at high spectral and time resolution to facilitate sub-arcsecond imaging and spectral line studies. In this paper, The authors provide an overview of the LoTSS. They outline the survey strategy, the observational status, the current calibration techniques, a preliminary data release, and the anticipated scientific impact. The preliminary images that they have released were created using a fully-automated but direction-independent calibration strategy and are significantly more sensitive than those produced by any existing large-area low-frequency survey. In excess of 44,000 sources are detected in the images that have a resolution of 25-arcseconds, typical noise levels of less than 0.5 mJy/beam, and cover an area of 381 square degrees in the region of the HETDEX Spring Field (Right Ascension 10<sup>h</sup> 45<sup>m</sup> 00<sup>s</sup> to 15<sup>h</sup> 30^m ^00<sup>s</sup> and Declination +45<sup>o</sup> 00' 00" to +57<sup>o</sup> 00' 00"). Source detection on the mosaics that are centered on each pointing was performed with PyBDSM (See <a href="http://www.astron.nl/citt/pybdsm/">http://www.astron.nl/citt/pybdsm/</a> for more details). In an effort to minimize contamination from artifacts, the catalog was created using a conservative 7-sigma detection threshold. Furthermore, as the artifacts are predominantly in regions surrounding bright sources, the authors utilized the PyBDSM functionality to decrease the size of the box used to calculate the local noise when close to bright sources, which has the effect of increasing the estimated noise level in these regions. Their catalogs from each mosaic are merged to create a final catalogue of the entire HETDEX Spring Field region. During this process, the authors remove multiple entries for sources by only keeping sources that are detected in the mosaic centered on the pointing to which the source is closest to the center. In the catalog, they provide the type of source, for which they used PyBDSM to distinguish isolated compact sources, large complex sources, and sources that are within an island of emission that contains multiple sources. In addition, they attempted to distinguish between sources that are resolved and unresolved in their images. The authors have provided a preliminary data release from the LOFAR Two-metre Sky Survey (LoTSS). This release contains 44,500 sources which were detected with a signal in excess of seven times the local noise in their 25" resolution images. The noise varies across the surveyed region but is typically below 0.5 mJy/beam and the authors estimate the catalog to be 90% complete for sources with flux densities in excess of 3.9 mJy/beam. This table was created by the HEASARC in February 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/598/A104">CDS Catalog J/A+A/598/A104</a> file lotss.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lofhatlas
- Title:
- LOFAR Radio Catalog of Herschel-ATLAS North Galactic Pole Field
- Short Name:
- LOFHATLAS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results of Low-Frequency Array (LOFAR) High-Band Array (HBA) observations of the Herschel-ATLAS North Galactic Pole (NGP) survey area. The survey the authors carried out, consisting of four pointings covering around 142 deg<sup>2</sup> of sky in the frequency range 126-173 MHz, does not provide uniform noise coverage but otherwise is representative of the quality of data to be expected in the planned LOFAR wide-area surveys, and has been reduced using recently developed 'facet calibration' methods at a resolution approaching the full resolution of the data sets (~10 x 6 arcsec) and an rms off-source noise that ranges from 100 µJy beam<sup>-1</sup> in the center of the best fields to around 2 mJy/beam at the furthest extent of their imaging. In the reference paper, the authors describe the imaging, cataloguing and source identification processes, and present some initial science results based on a 5-sigma source catalog. These include (i) an initial look at the radio/far-infrared correlation at 150 MHz, showing that many Herschel sources are not yet detected by LOFAR; (ii) number counts at 150 MHz, including, for the first time, observational constraints on the numbers of star-forming galaxies; (iii) the 150-MHz luminosity functions for active and star-forming galaxies, which agree well with determinations at higher frequencies at low redshift, and show strong redshift evolution of the star-forming population; and (iv) some discussion of the implications of these observations for studies of radio galaxy life cycles. The NGP field was observed in four separate pointings, chosen to maximize the area of sky covered, with the LOFAR HBA as part of the Surveys Key Science project. These observations used the HBA_DUAL_INNER mode, meaning that the station beams of core and remote stations roughly matched each other and giving the widest possible field of view. The first observation, which was made early on in LOFAR operations, was of slightly longer duration (~10 h) than the others (~8 h). International stations were included in some of the observations in 2014 but were not used in any of the authors' analysis, which uses only the Dutch array. The author were interested in imaging in several separate frequency ranges (which are referred to hereafter as 'spectral windows'), since they wanted to be able to measure in-band spectral indices for detected sources. In addition, facet calibrating in different spectral windows could be done in parallel, speeding the processing up considerably. Accordingly, they chose to facet calibrate with six spectral windows, each made up of four bands and thus containing about 8 MHz of bandwidth: <pre> Spectral Nominal Frequency Frequency Range Window (MHz) (MHz) 1 130 126 - 134 2 138 134 - 142 3 146 142 - 150 4 154 150 - 158 5 161 158 - 166 6 169 166 - 173 </pre> The final source catalog was made by combining the four per-field catalogs. Ideally, the authors would have combined the images of each field and done source finding on a mosaicked image, but this proved computationally intractable given the very large image cubes that result from having six spectral windows. They therefore merged the catalogs by identifying the areas of sky where there is overlap between the fields and choosing those sources which are measured from the region with the best rms values. This should ensure that there are no duplicate sources in the final catalog. The final master catalogue contains 17,132 sources and is derived from images covering a total of 142.7 deg<sup>2</sup> of independently imaged sky, with widely varying sensitivity. Total HBA-band (150-MHz) flux densities of catalogued sources detected using the PYBDSM software and a 5-sigma detection threshold range from a few hundred µJy to 20 Jy, with a median of 10 mJy. The authors examined all sources in the initial master catalog for associations with sources in other surveys, for rejection as artifacts, and for optical identifications, as described in detail in Section 3.5 of the reference paper. The final outcomes of this process were (a) an associated, artifact-free catalog of 15,292 sources, all of which the authors believe to be real physical objects which is contained in the present HEASARC table, and (b) a catalog of 6,227 objects with plausible, single optical identifications with Sloan Digital Sky Survey (SDSS) sources, representing an identification fraction of just over 40 per cent. (Note that around 50 sources with more than one equally plausible optical identification are excluded from this catalog; further observation would be required to disambiguate these sources). This table was created by the HEASARC in April 2018, based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/462/1910">CDS Catalog J/MNRAS/462/1910</a> file tablea1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lorcat
- Title:
- Low-Frequency Radio Catalog of Flat-Spectrum Sources
- Short Name:
- LORCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- A well-known property of the gamma-ray sources detected by Cos-B in the 1970s, by the Compton Gamma-Ray Observatory in the 1990s, and recently by the Fermi Gamma-ray Observatory is the presence of radio counterparts, particularly for those associated with extragalactic objects. This observational evidence is the basis of the radio/gamma-ray connection established for the class of active galactic nuclei known as blazars. In particular, the main spectral property of the radio counterparts associated with gamma-ray blazars is that they show a flat spectrum in the GHz frequency range. The authors' recent analysis dedicated to search for blazar-like candidates as potential counterparts for the unidentified gamma-ray sources allowed them to extend the radio/gamma-ray connection in the MHz regime. They also showed that blazars below 1 GHz maintain flat radio spectra. Thus, on the basis of these new results, the authors have assembled a low-frequency radio catalog of flat-spectrum sources built by combining the radio observations of the Westerbork Northern Sky Survey (WENSS) and of the Westerbork in the southern hemisphere (WISH) catalogs with those of the NRAO Very Large Array Sky survey (NVSS). This catalog could be used in the future to search for new, unknown blazar-like counterparts of gamma-ray sources. First, the authors found NVSS counterparts of Westerbork Synthesis Radio Telescope (WSRT) radio sources, and then they selected flat-spectrum radio sources according to a new spectral criterion, specifically defined for radio observations performed below 1 GHz. In their paper, they also describe the main properties of the catalog listing 28,358 radio sources with spectral indices between 1400 and 325/352 MHz between -1.0 and +0.4, and their log N - log S distributions. Finally, a comparison with the Green Bank 6 cm radio source catalog was performed so as to investigate the spectral shape of the low-frequency flat-spectrum radio sources at higher frequencies. This table was created by the HEASARC in July 2014 based on a machine-readable version of Table 1 from the reference paper which was obtained from the ApJS web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mwmc
- Title:
- Milky Way Molecular Clouds from CO Measurements
- Short Name:
- MWMC
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This study presents a catalog of 8107 molecular clouds that covers the entire Galactic plane and includes 98% of the <sup>12</sup>CO emission observed within b +/- 5 deg. The catalog was produced using a hierarchical cluster identification method applied to the result of a Gaussian decomposition of the Dame+ (2001ApJ...547..792D) data. The total H<sub>2</sub> mass in the catalog is 1.2 x 10<sup>9</sup> M<sub>sun</sub>, in agreement with previous estimates. The authors find that 30% of the sight lines intersect only a single cloud, with another 25% intersecting only two clouds. The most probable cloud size is R~30pc. In contrast with the general idea, the authors find a rather large range of values of surface densities, Sigma = 2 to 300 M<sub>sun</sub>/pc<sup>2</sup>, and a systematic decrease with increasing Galactic radius, R<sub>gal</sub>. The cloud velocity dispersion and the normalization sigma<sub>0</sub> = sigma<sub>v</sub> / R<sup>1/2</sup> both decrease systematically with R<sub>gal</sub>. When studied over the whole Galactic disk, there is a large dispersion in the line width-size relation and a significantly better correlation between sigma<sub>v</sub> and SigmaR. The normalization of this correlation is constant to better than a factor of two for R<sub>gal</sub> < 20kpc. This relation is used to disentangle the ambiguity between near and far kinematic distances. The authors report a strong variation of the turbulent energy injection rate. In the outer Galaxy it may be maintained by accretion through the disk and/or onto the clouds, but neither source can drive the 100 times higher cloud-averaged injection rate in the inner Galaxy. The data set used in this catalog come from that of Dame+ (2001ApJ...547..792D). Those authors combined observations obtained over a period of 20 yr with two telescopes, one in the north (first located in New York City and then moved to Cambridge, Massachusetts) and one in the south (Cerro Tololo, Chile). These 1.2m telescopes have an angular resolution of ~8.5' at 115GHz, the frequency of the <sup>12</sup>CO 1-0 line. For the current study the authors used the data set covering the whole Galactic plane with +/- 5 deg in Galactic latitude. This table was created by the HEASARC in March 2019 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/834/57">CDS Catalog J/ApJ/834/57</a> file table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mitgb6cm
- Title:
- MIT-Green Bank 5-GHz Survey Catalog
- Short Name:
- MIT-GB
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The MIT-Green Bank 5 GHz Survey Catalog was produced from four separate surveys with the National Radio Astronomy Observatory (NRAO) 91m transit telescope, the results from which were presented in papers by Bennett et al., 1986ApJS...61....1B (MG1), Langston et al., 1990ApJS...72..621L (MG2), Griffith et al., 1990ApJS...74..129G (MG3), and Griffith et al. 1991ApJS...75..801G (MG4). The sky coverage of the various surveys is: <pre> 00h < RAB < 24h, -00d30'13" < DECB < +19d29'47" for MG1 04h < RAJ < 21h, +17.0d < DECJ < +39d09' for MG2 16h30m < RAB < 05h, +17d < DECB < +39d09' for MG3 15h30m < RAB < 02h30m, +37.00d < DECB < +50d58'48" for MG4 </pre> where RAB and DECB refer to B1950 coordinates, and RAJ and DECJ refer to J2000 coordinates. The catalog contains 20344 sources detected with a signal-to-noise ratio greater than 5 and 3836 possible detections (MG1) with a signal-to-noise ratio less than 5. Spectral indices are computed for MG1 sources also identified in the Texas 365 MHz survey (Douglas et al. 1980, Univ. Texas Pub. Astr. No. 17), and for MG1-MG4 sources also identified in the NRAO 1400 MHz Survey (Condon and Broderick 1985, AJ, 90, 2540 = 1985AJ.....90.2540C). This online catalog was created by the HEASARC in October 2003 based on CDS catalog VIII/52B (the file mgcat.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mgps2
- Title:
- Molonglo Galactic Plane Survey 2nd Epoch Compact Source Catalog
- Short Name:
- MGPS2
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the Molonglo Galactic Plane Survey 2nd Epoch (MGPS-2) Compact Source Catalog. The MGPS-2 was carried out with the Molonglo Observatory Synthesis Telescope (MOST) at a frequency of 843 MHz and with a restoring beam of 45" x 45" cosec |(delta)|, where delta is the declination, making it the highest resolution large-scale radio survey of the southern Galactic plane to date. It covers the range |b| < 10 degrees and 245 < l < 365 degrees, where l and b are the Galactic longitude and latitude, and is the Galactic counterpart to the SUMSS (CDS Cat. VIII/81) Catalog which covers that portion of the southern sky with delta < -30 degrees, |b| > 10 degrees. This version of the catalog (15-Aug-2007) consists of 48850 compact sources, made by fitting elliptical Gaussians in the MGPS-2 mosaics to a limiting peak brightness of 10 mJy/beam. The authors used a custom method (described in the associated reference publication) to remove extended sources from the catalog. Positions in the catalog are accurate to 1" - 2". The authors have carried out an analysis of the compact source density across the Galactic plane and find that the source density is not statistically higher than the density expected from the extragalactic source density alone. See <a href="http://www.astrop.physics.usyd.edu.au/mosaics">http://www.astrop.physics.usyd.edu.au/mosaics</a> for access to the MGPS-2 mosaic images. This HEASARC table was created in January 2008 based on CDS catalog J/MNRAS/382/382 file mgpscat.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mostatlas
- Title:
- Molonglo Observatory Synthesis Telescope ATLAS 843-MHz Source Catalog
- Short Name:
- MOSTATLAS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- At the faintest radio flux densities (S<sub>1.4</sub> < 10 mJy), conflicting results have arisen regarding whether there is a flattening of the average spectral index between a low radio frequency (325 or 610 MHz) and, for example, 1.4 GHz. The authors present a new catalog of 843-MHz radio sources in the European Large Area ISO Survey-South 1 (ELAIS-S1) field, which contains the sources, their Australia Telescope Large Area Survey (ATLAS) counterparts and the spectral index distribution of the sources as a function of flux density. The authors do not find any statistically significant evidence for a trend towards flatter spectral indices with decreasing flux density. In the reference paper, they investigate the spectral index distribution with redshift for those sources with reliable redshifts and explore the infrared properties. An initial sample of faint compact steep-spectrum sources in ATLAS are also presented, with a brief overview of their properties. To obtain low-radio-frequency (843-MHz) data within the ATLAS ELAIS-S1 region (Middelberg et al. 2008, AJ, 135, 1276, the tables from which are available as the ATLASESID and ATLASESCPT tables in the HEASARC database), the authors used the Molonglo Observatory Synthesis Telescope (MOST). They have made 31 separate 12-h observations taken with MOST, which were combined into a single image with a spatial resolution of 62 arcsec x 43 arcsec. This table was created by the HEASARC in January 2013 based on the CDS Catalog J/MNRAS/421/1644 file table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mostsnrcat
- Title:
- Molonglo Observatory Synthesis Telescope Supernova Remnant Catalog
- Short Name:
- MOSTSNRCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- A catalog of supernova remnants (SNR) in the southern Galaxy within the Galactic Plane area 245 degrees <= galactic longitude l_II <= 355 degrees, galactic latitude |b_II| <~ 1.5 degrees has been produced from observations made in a series of 650 overlapping fields at 0.843 GHz (35.6 cm) with a spatial resolution of 43" using the Molonglo Observatory Synthesis Telescope (MOST). This table contains information on 57 known SNR (listed in Table MSC.A of the reference paper), 18 SNR newly discovered in this survey (Table MSC.B), 16 possible SNR (Table MSC.C), and 2 reclassified SNR (discussed in Section 3.3 of the reference paper), for a total of 93 SNR. This table was created by the HEASARC in March 2007 based on the CDS table J/A+AS/118/329, file msc.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mrc
- Title:
- Molonglo Reference Catalog of Radio Sources
- Short Name:
- MRC
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog is a version of the 1990 issue of the "Molonglo Reference Catalog of Radio Sources" (MRC). The MRC is one of the largest homogeneous catalogs of radio sources, containing 12,141 discrete sources with flux densities greater than 0.7 Jy in the declination range +18.5 degrees to -85 degrees (1950 coordinates) and excluding regions within 3 degrees of the Galactic equator. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/magpis
- Title:
- Multi-Array Galactic Plane Imaging Survey
- Short Name:
- MAGPIS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Multi-Array Galactic Plane Imaging Survey (MAGPIS) maps portions of the first Galactic quadrant with an angular resolution, sensitivity, and dynamic range that surpass existing radio images of the Milky Way by more than an order of magnitude. The source detection threshold at 20 cm is in the range 1-2 mJy over the 85% of the survey region (Galactic longitudes from 5 to 32 degrees and Galactic latitudes within 0.8 degrees of the Galactic plane) not covered by bright extended emission; the angular resolution is ~6". Over 3000 discrete sources (diameters mostly <30") and ~400 diffuse emission regions are catalogued. Additional information and data products, including full-resolution 20 cm images, complementary 90 cm images, regridded MSX 21 micron images, an image atlas of diffuse emission regions are available at the MAGPIS web site <a href="http://third.ucllnl.org/gps">http://third.ucllnl.org/gps</a> This table was created by the HEASARC in June 2006 based on machine-readable versions of Tables 2 and 3 of the above reference which were obtained from the electronic Astronomical Journal web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mwacs
- Title:
- Murchison Widefield Array Commissioning Survey Compact Low-Frequency Source Ctlg
- Short Name:
- MWACS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Murchison Widefield Array Commissioning Survey (MWACS) is a ~6100 deg<sup>2</sup> 104 - 196 MHz radio sky survey performed with the Murchison Widefield Array during instrument commissioning between 2012 September and 2012 December. The data were taken as meridian drift scans with two different 32-antenna sub-arrays that were available during the commissioning period. The data were combined in the visibility plane before being imaged, and then mosaicked. The survey covers approximately 20.5<sup>h</sup> < RA < 8.5<sup>h</sup>, -58<sup>o</sup> < Dec < -14<sup>o</sup> over three frequency bands centred on 119, 150 and 180 MHz. The survey has 3-arcminute angular resolution and a typical noise level of 40 mJy/beam, with reduced sensitivity near the field boundaries and bright sources. The catalog consists of flux density and spectral index measurements for 14,110 sources, extracted from the mosaics, 1,247 of which are sub-components of complexes of sources. This table was created by the HEASARC in December 2014 based on CDS catalog VIII/98 file mwacs.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mwak2f1lfc
- Title:
- Murchison Widefield Array Low-Frequency Radio Survey of Kepler K2 Field 1
- Short Name:
- MWAK2F1LFC
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results from the first dedicated radio continuum survey of a Kepler K2 mission field, Field 1, covering the North Galactic Cap. The survey was wide-field, contemporaneous, multi-epoch, and multi-resolution in nature and was conducted at low radio frequencies between 140 and 200 MHz. The multi-epoch and ultra-wide-field (but relatively low-resolution) part of the survey was provided by 15 nights of observation using the Murchison Widefield Array (MWA) over a period of approximately a month, contemporaneous with K2 observations of this field. The multi-resolution aspect of the survey was provided by the low-resolution (4 arcminutes) MWA imaging, complemented by non-contemporaneous but much higher resolution (20 arcseconds) observations using the Giant Metrewave Radio Telescope (GMRT). The survey is, therefore, sensitive to the details of radio structures across a wide range of angular scales. Consistent with other recent low radio frequency surveys, no significant radio transients or variables were detected in the survey. The resulting source catalogs consist of 1,085 and 1,468 detections in the two MWA observation bands (centered at 154 and 185 MHz, respectively) and 7445 detections in the GMRT observation band (centered at 148 MHz), over 314 square degrees. The survey is presented as a significant resource for multi-wavelength investigations of the more than 21,000 target objects in the K2 field. In the reference paper, the authors briefly examined their survey data against K2 target lists for dwarf star types (stellar types M and L) that had been known to produce radio flares. This survey included contemporaneous observations of the K2 Field 1 made with the MWA and historical (from 2010-2012) observations made with the Tata Institute of Fundamental Research (TIFR) GMRT Sky Survey (TGSS; see <a href="http://tgss.ncra.tifr.res.in/">http://tgss.ncra.tifr.res.in/</a>), via the TGSS Alternative Data Release 1 (ADR1; Intema et al. 2016, in prep.). The MWA and GMRT are radio telescopes operating at low radio frequencies (approximately 140-200 MHz for the work described here). The K2 mission Campaign 1 was conducted on Field 1 (center at J2000.0 coordinates RA of 11:35:45.51 and Dec of +01:25:02.28;), covering the North Galactic Cap, between 2014 May 30 and August 21. The details of the MWA observations are described in Table 1 of the reference paper (available at <a href="ftp://cdsarc.u-strasbg.fr/pub/cats/J/AJ/152/82/table1.dat">ftp://cdsarc.u-strasbg.fr/pub/cats/J/AJ/152/82/table1.dat</a>), showing the 15 observations conducted over a period of approximately one month in 2014 June and July. All observations were made in a standard MWA imaging mode with a 30.72-MHz bandwidth consisting of 24 contiguous 1.28-MHz "coarse channels", each divided into 32 "fine channels" each of 40-kHz bandwidth (a total of 768 fine channels across 30.72 MHz). The temporal resolution of the MWA correlator output was set to 0.5s. All observations were made in full polarimetric mode, with all Stokes parameters formed from the orthogonal linearly polarized feeds. Observations were made at two center frequencies, 154.88 and 185.60 MHz, with two 296-s observations of the K2 field at each frequency on each night of observation, accompanied by observations of one of three calibrators (Centaurus A, Virgo A, or Hydra A) at each frequency, with 112-s observations. The observed fields were tracked, and thus, due to the fixed delay settings available to point the MWA primary beam, the tracked RA and Dec changes slightly between different observations (always a very small change compared to the MWA field of view). The total volume of MWA visibility data processed was approximately 2.2 TB. The synthesized beam at 154 MHz is approximately 4.6 x 4.2 arcminutes at a position angle of 105 degrees, and approximately 4 x 3 arcminutes at a position angle of 109 degrees at 185 MHz. The 154 MHz images have a typical noise of 100 mJy/beam, while the 184 MHz images have a typical noise of 70 mJy/beam. A source catalog was produced from each of the two frequencies of MWA data and given in Table 2 of the reference paper. The final set of MWA images after source finding yielded a total of 1,085 radio sources at 154 MHz, and 1,471 sources at 185 MHz over 314 square degrees, at an angular resolutions of ~4 arcminutes: this MWA catalog is contained in this HEASARC table, which thus has 1,085 + 1,471 = 2,556 entries. The GMRT images, after source finding, yielded a total of 7,445 radio sources over the same field, at an angular resolution of ~0.3 arcminutes: the GMRT catalog is contained in a separate HEASARC table GMRTK2F1LF which is available at <a href="http://heasarc.gsfc.nasa.gov/W3Browse/radio-catalog/gmrtk2f1lf.html">http://heasarc.gsfc.nasa.gov/W3Browse/radio-catalog/gmrtk2f1lf.html</a>. Thus, the overall survey covers multiple epochs of observation, spans approximately 140-200 MHz, is sensitive to structures on angular scales from arcseconds to degrees, and is contemporaneous with the K2 observations of the field over a period of approximately one month. This table was created by the HEASARC in December 2016 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/152/82">CDS Catalog J/AJ/152/82</a> file table2.dat (the MWA Kepler 2 Field 1 source catalog). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mwa32thgl
- Title:
- Murchison Widefield Array 32-T Low-Frequency Source Catalog
- Short Name:
- MWA32THGL
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Murchison Widefield Array (MWA) is a new low-frequency, wide-field-of-view radio interferometer under development at the Murchison Radio-astronomy Observatory in Western Australia. The authors have used a 32 element MWA prototype interferometer (MWA-32T) to observe two 50 degree diameter fields in the southern sky, covering a total of ~ 2700 deg<sup>2</sup>, in order to evaluate the performance of the MWA-32T, to develop techniques for epoch of reionization experiments, and to make measurements of astronomical foregrounds. They developed a calibration and imaging pipeline for the MWA-32T, and used it to produce ~15 arcminutes angular resolution maps of the two fields in the 110-200 MHz band. The authors perform a blind source extraction using these confusion-limited images, and detect 655 sources at high significance with an additional 871 lower significance source candidates. They compare these sources with existing low-frequency radio surveys in their paper in order to assess the MWA-32T system performance, wide-field analysis algorithms, and catalog quality. Their source catalog is found to agree well with existing low-frequency surveys in these regions of the sky and with statistical distributions of point sources derived from Northern Hemisphere surveys; it represents one of the deepest surveys to date of this sky field in the 110-200 MHz band. Observations were conducted with the MWA-32T in 2010 March during a two-week campaign (X13). Data were taken in three 30.72 MHz sub-bands centered at 123.52 MHz, 154.24 MHz, and 184.96 MHz in order to give (nearly) continuous frequency coverage between ~ 110 MHz and ~ 200 MHz. The observing time was divided between two fields. One field was centered on the bright extragalactic source Hydra A at RA (J2000) = 9<sup>h</sup> 18<sup>m</sup> 6<sup>s</sup>, Dec (J2000) = -12^o 5' 45" to facilitate calibration. The other covered the Epoch of Reionization (EoR) field 2, centered at RA (J2000) = 10<sup>h</sup> 20<sup>m</sup> 0<sup>s</sup>, Dec (J2000) = -10<sup>o</sup> 0' 0". The EoR2 field is one of two fields at high Galactic latitude that have been identified by the MWA Collaboration as targets for future EoR experiments. Although the centers of the Hydra A and EoR2 fields are separated by 15.3 degrees, there is considerable overlap between them since the half-power beam width of the primary beam is ~ 25 degrees at 150 MHz. Table 1 in the reference paper gives a journal of the observations. This table contains 648 radio sources which were detected in the full-band average map at or above a signal-to-noise ratio of 5. This table was created by the HEASARC in October 2012, based on an electronic version of table 2 from the reference paper as obtained from the ApJ website. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/wbhgp20cm
- Title:
- New Catalog of Compact 20cm Sources in the Galactic Plane
- Short Name:
- WBH20cmGP
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the New Catalog of Compact Radio (20-cm) Sources in the Galactic Plane of White et al. (2005). Archival data were combined with more recent observations of the Galactic plane using the Very Large Array to create two new catalogs of compact centimetric radio sources. The 20-cm source catalog contained here covers a longitude range from -20 to +120 degrees in Galactic longitude l; the latitude coverage varies from b = +/- 0.8 to +/- 2.7 degrees. The total survey area is about 331 square degrees; coverage is 90% complete at a flux density threshold of about 14 mJy, and over 5000 sources are recorded. The 6-cm catalog (also available in the HEASARC Browse system as the table WBHGP6CM) covers 43 square degrees in the region -10 degrees < l <42 degrees, |b| < 0.4 degrees to a 90% completeness threshold of 2.9 mJy; over 2700 sources are found. Both surveys have an angular resolution of about 6". These catalogs provide a 30% (at 20 cm) to 50% (at 6 cm) increase in the number of high-reliability compact sources in the Galactic plane, as well as greatly improved astrometry, uniformity, and reliability; they should prove useful for comparison with new mid- and far-infrared surveys of the Milky Way. The images from which this catalog was constructed are available at the MAGPIS web site, <a href="http://third.ucllnl.org/gps">http://third.ucllnl.org/gps</a> This table was created by the HEASARC in July 2006 based on the combination of CDS tables J/AJ/130/586 table3.dat and table4.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/wbhgp6cm
- Title:
- New Catalog of Compact 6cm Sources in the Galactic Plane
- Short Name:
- WBH6cmGP
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the New Catalog of Compact Radio (6-cm) Sources in the Galactic Plane of White et al. (2005). Archival data were combined with more recent observations of the Galactic plane using the Very Large Array to create two new catalogs of compact centimetric radio sources. The 20-cm source catalog (available in the HEASARC Browse system as the table WBHGP20CM) covers a longitude range from -20 to +120 degrees in Galactic longitude l; the latitude coverage varies from b = +/- 0.8 to +/- 2.7 degrees. The total survey area is about 331 square degrees; coverage is 90% complete at a flux density threshold of about 14 mJy, and over 5000 sources are recorded. The 6-cm catalog described here covers 43 square degrees in the region -10 degrees < l <42 degrees, |b| < 0.4 degrees to a 90% completeness threshold of 2.9 mJy; over 2700 sources are found. Both surveys have an angular resolution of about 6". These catalogs provide a 30% (at 20 cm) to 50% (at 6 cm) increase in the number of high-reliability compact sources in the Galactic plane, as well as greatly improved astrometry, uniformity, and reliability; they should prove useful for comparison with new mid- and far-infrared surveys of the Milky Way. The images from which this catalog was constructed are available at the MAGPIS web site, <a href="http://third.ucllnl.org/gps">http://third.ucllnl.org/gps</a> This table was created by the HEASARC in July 2006 based on the combination of CDS tables J/AJ/130/586 table5.dat and table6.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ncp21cma
- Title:
- North Celestial Pole Region Radio Sources Detected by the 21cm Array
- Short Name:
- NCP21CMA
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the catalog of 624 radio sources detected around the North Celestial Pole (NCP) with the 21 Centimeter Array (21CMA), a radio interferometer dedicated to the statistical measurement of the epoch of reionization (EoR). The data are taken from a 12-hr observation made on 2013 April 13, with a frequency coverage from 75 to 175 MHz and an angular resolution of ~4 arcminutes. The catalog includes flux densities at eight sub-bands across the 21CMA bandwidth and provides the in-band spectral indices for the detected sources. To reduce the complexity of interferometric imaging from the so-called "w" term and ionospheric effects, the present analysis is restricted to the east-west baselines within 1500 m only. 624 radio sources are found within 5 degrees around the NCP down to ~0.1 Jy (100 mJy). These source counts are compared, and also exhibit a good agreement, with deep low-frequency observations made recently with the GMRT and MWA. In particular, for fainter radio sources below ~1 Jy, the authors find a flattening trend of source counts toward lower frequencies. While the thermal noise (~0.4 mJy) is well controlled to below the confusion limit, the dynamical range (~10<sup>4</sup>) and sensitivity of current 21CMA imaging are largely limited by calibration and deconvolution errors, especially the grating lobes of very bright sources, such as 3C061.1, in the NCP field, which result from the regular spacings of the 21CMA. The authors note that particular attention should be paid to the extended sources, and their modeling and removal may constitute a large technical challenge for current EoR experiments. Their analysis may serve as a useful guide to the design of next generation low-frequency interferometers like the Square Kilometre Array (SKA). The 21CMA is a ground-based radio interferometer dedicated to the detection of the EoR. The array, sited in the Ulastai valley of western China, consists of 81 pods or stations, and a total of 10,287 log-periodic antennas are deployed in two perpendicular arms along the east-west (6.1 km) (see Figure 1 in the reference paper) and north-south (4 km) directions, respectively. The spacing of these 81 pods is chosen such that a sufficiently large number of redundant baselines and a good uniform UV coverage can both be guaranteed. Each antenna element has 16 pairs of dipoles with lengths varying from 0.242 to 0.829 m, optimized to cover a frequency range of 50-200 MHz, which gives rise to an angular resolution of 3 arcminutes at 200 MHz. All of the antennas are fixed on the ground and point at the NCP for the sake of simplicity and economy. In the current work, the radio point sources observed with the 40 pods of the 21 Centimeter Array (21CMA) E-W baselines in an integration of 12 hours made on 2013 April 13 centered on the North Celestial Pole (NCP) are presented. An extra deep sample with a higher sensitivity from a longer integration time of up to years will be published later. The authors have detected a total of 624 radio sources over the central field within 3 degrees in a frequency range of 75-175 MHz band and in the outer annulus from 3-5 degrees in the 75-125 MHz band. By performing a Monte-Carlo simulation, the authors estimate a completeness of 50% at a flux density of ~0.2 Jy. This table was created by the HEASARC in May 2017 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/832/190">CDS Catalog J/ApJ/832/190</a> file table3.dat. 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/nvss
- Title:
- NRAO VLA Sky Survey Catalog
- Short Name:
- NVSS
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the National Radio Astronomy Observatory (NRAO) Very Large Array (VLA) Sky Survey, the so-called NVSS Catalog. The NVSS Catalog covers the sky north of the J2000.0 Declination of -40 degrees (82% of the celestial sphere) at 1.4 GHz. The principal data products of the NVSS were (1) a set of 2326 4 degree by 4 degree continuum "cubes" with three planes containing Stokes I, Q, and U images, plus (2) a catalog of almost 2 million discrete sources stronger than a flux density S of about 2.5 mJy. The images all have 45 arcsecond FWHM angular resolution and nearly uniform sensitivity. Their rms brightness fluctuations are approximately 0.45 mJy/beam = 0.14 K (Stokes I) and approximately 0.29 mJy/beam = 0.09 K (Stokes Q and U). The rms uncertainties in right ascension and declination vary from <= ~1 arcsecond for the 400,000 sources stronger than 15 mJy to 7 arcseconds at the survey limit. The NVSS was made as a service to the astronomical community. All data products, user software, and updates were released via the World-Wide Web as soon as they were produced and verified. For more complete information on the NVSS, please refer to the NVSS website at <a href="http://www.cv.nrao.edu/nvss/">http://www.cv.nrao.edu/nvss/</a> This table was created by the HEASARC in October 2002 based on the file <a href="ftp://ftp.cv.nrao.edu/nvss/CATALOG/NVSSCatalog.text.gz">ftp://ftp.cv.nrao.edu/nvss/CATALOG/NVSSCatalog.text.gz</a> provided by the NVSS Catalog's authors. It was updated by the HEASARC in June 2009 to fix a problem with the original ingest in which the leading digit of some flux fields was lost. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cratesocrap
- Title:
- OCRA-p Survey of a Subset of CRATES Sources
- Short Name:
- CRATESOCRAP
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Knowledge of the population of radio sources in the range ~ 2-200 GHz range is important for understanding their effects on measurements of the cosmic microwave background power spectrum. This table contains measurements of the 30-GHz flux densities of 605 radio sources from the Combined Radio All-sky Targeted Eight-GHz Survey (CRATES), which have been made with the One Centimetre Receiver Array-prototype (OCRA-p) on the Torun 32-m telescope. The flux densities of sources that were also observed by Wilkinson Microwave Anisotropy Probe (WMAP) and previous OCRA surveys are in broad agreement with those reported here, however a number of sources display intrinsic variability. The authors find a good correlation between the 30 GHz and Fermi gamma-ray flux densities for sources in common. In their paper, they examine the radio spectra of all observed sources and report a number of gigahertz-peaked and inverted spectrum sources. These measurements will be useful for comparison to those from the Low Frequency Instrument of the Planck satellite, which will make some of its most sensitive observations in the region covered here. The selection criteria for the subsample of CRATES sources observed by the OCRA-p are given in Section 2 of the reference paper (q.v.). Plots of the measurements of each source over time and the aggregated source spectra between 26 MHz and 150 GHz are available online at the authors' web site: <a href="http://www.jb.man.ac.uk/research/ocra/crates/">http://www.jb.man.ac.uk/research/ocra/crates/</a>. This table was created by the HEASARC in May 2011 based on an electronic version of Table 3 of the reference paper which was obtained from the authors' web site <a href="http://www.jb.man.ac.uk/research/ocra/crates/">http://www.jb.man.ac.uk/research/ocra/crates/</a>. Notice that the version here is the 10-Jan-2011 version which contains corrections to the 30-GHz flux densities and their errors of ~ 1% in the calibration and the application of the gain-elevation curve. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ovro31ghz
- Title:
- Owens Valley Radio Observatory 40-m 31-GHZ Radio Source Catalog
- Short Name:
- OVRO31GHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The 100m Robert C. Byrd Green Bank Telescope (GBT) and the 40m Owens Valley Radio Observatory (OVRO) telescope have been used to conduct a 31-GHz survey of 3165 known extragalactic radio sources over 143 deg<sup>2</sup> of the sky. Target sources were selected from the NRAO VLA Sky Survey (NVSS) in fields observed by the Cosmic Background Imager (CBI); most are extragalactic active galactic nuclei (AGNs) with 1.4-GHz flux densities of 3-10 mJy. Using a maximum-likelihood analysis to obtain an unbiased estimate of the distribution of the 1.4 - 31 GHz spectral indices of these sources, the authors find a mean 31 - 1.4 GHz flux ratio of 0.110 +/- 0.003 corresponding to a spectral index alpha = -0.71+/-0.01 (S<sub>nu</sub> ~ nu<sup>alpha</sup>); 9.0% +/- 0.8% of the sources have alpha > -0.5 and 1.2% +/- 0.2% have alpha > 0. By combining this spectral-index distribution with 1.4GHz source counts, the authors predict 31-GHz source counts in the range 1 mJy <S<sub>31</sub> < 4 mJy, N(>S<sub>31</sub>) = (16.7+/-1.7)deg<sup>-2</sup>(S<sub>31</sub>/1mJy)<sup>(-0.80+/-0.07)</sup>. In this study, the authors present a detailed characterization of the impact of the discrete source foreground on arcminute-scale 31-GHz anisotropy measurements based upon two observational campaigns. The first campaign (the results of which are given in this table) was carried out with the OVRO 40m telescope at 31 GHz from 2000 September through 2002 December. The second campaign (the results of which are given in the GBT31GHZ table) used the GBT from 2006 February to May. A companion paper (Sievers et al. 2009arXiv0901.4540S) presents the five-year CBI total intensity power spectrum incorporating the results of the point-source measurements discussed here. Reported error bars include a 10% and 5% rms gain uncertainty for GBT and OVRO measurements, respectively. Sources detected at greater than 4 sigma at 31 GHz are flagged (detection_flag = 'Y'); for this calculation, the random gain uncertainty was excluded. In all 3165 sources were observed. The GBT catalog (the HEASARC GBT31GHZ table) contains 1490 sources. Of the 2315 useful OVRO observations many of the non-detections (and a few detections) were superceded by more sensitive GBT observations; the OVRO catalog contained in the present table therefore contains data on 1675 sources. The detection rate of the OVRO measurements was 11%, and that of the GBT measurements 25%. In all, 18% of the sources were detected at 31 GHz. This table was created by the HEASARC in June 2012 based on CDS Catalpog J/ApJ/704/1433 file table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pmn
- Title:
- Parkes-MIT-NRAO (PMN) Surveys
- Short Name:
- PMN
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The PMN database contains data from the Parkes-MIT-NRAO (PMN) Southern, Zenith, Tropical and Equatorial surveys. These surveys were made using the Parkes 64-m radio telescope at a frequency of 4850 Hz with the NRAO multibeam receiver mounted at the prime focus (for a full description of the observations see Griffith & Wright, 1993, Paper I). These surveys had a spatial resolution (full width half-maximum: FWHM) of approximately 4.2 arcminutes and were made during 1990 June and November. The PMN surveys were divided into several zones. These zones are listed below, together with approximate flux limits and survey areas: <pre> Zone Name DEC limits (degrees) Flux limits Area (sr) SOUTHERN -87.5< dec <-37 20 to 50 mJy 2.50 ZENITH -37 < dec <-29 72 mJy 0.67 TROPICAL -29 < dec < -9.5 42 mJy 2.01 EQUATORIAL -9.5< dec <+10.0 40 mJy 1.90 </pre> A point source catalog was compiled directly from each of the survey zones by using an optimum filter method, as described by Griffith & Wright in detail in Paper 1. In addition, a set of images was produced for each zone in a manner very similar to that used by Condon et al. for the northern survey (CDS Catalog VIII/40): See e.g. Paper 4. These maps have an effective resolution (FWHM) of about 5 arcmin. For more details, refer to the publications listed in the References Section for the relevant zone. This updated version of the PMN database was created by the HEASARC in January 2001 based on CDS Catalog VIII/38. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pkscat90
- Title:
- Parkes Southern Radio Source Catalog, Version 1.01
- Short Name:
- Parkes
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- PKSCAT90 is the Parkes Catalog (1990) and consists of radio and optical data for 8,264 radio sources. It covers essentially all the sky south of declination +27 degrees but largely excludes the Galactic Plane and the Magellanic Cloud regions. The latter zones have been the subject of other, specialist surveys. A few data errors in Version 1.00 have been corrected in the present edition (see below). This version of the Parkes Radio Source Catalog is entitled "PKSCAT90 Version 1.01." The original Parkes radio catalog was compiled from major radio surveys with the Parkes radiotelescope at frequencies of 408 MHz and 2700 MHz. This work spanned a period of nearly 20 years and was undertaken largely by John Bolton and his colleagues. Since then, improved positions, optical identifications, and redshifts have been obtained for many of the sources in the catalog. Furthermore, flux densities at several frequencies have supplemented the original surveys so that the measurements now cover the frequency range 80-22,000 MHz. However, coverage at the highest frequencies is still sparse. Important contributions to the usefulness of the catalog have been radio data from the Molonglo 408-MHz survey and the 80-MHz Culgoora measurements of Slee et al. PKSCAT90 should thus be regarded as a compendium of radio and optical data about southern radio sources. However, at the moment, it contains only sources originally found in the Parkes 2700-MHz survey (see e.g. Part 14, Bolton et al, 1979, Aust J Phys, Astrophys Suppl, No. 46 and references therein.) The original radio survey data of the catalog and the optical identifications have been published in a series of papers in the Australian Journal of Physics (see above reference). The associated optical spectral data on which redshifts were obtained has also been published, mainly in Astrophysical Journal and Monthly Notices of the Royal Astronomical Society. About the completeness levels of the catalog in various parts of the sky: users should note that the sky zone between -4 and +4 degrees has been the subject of a re-survey and is now complete to 0.25 Jy. The author Alan Wright notes that "PKSCAT90 was produced at a time when relational databases were in their infancy. In the future we anticipate making the individual data sources available separately -- through such search systems as SIMBAD -- rather than in an 'omnibus' catalog like PKSCAT90. For both the Northern and Southern hemispheres, superior and deeper finding surveys now exist: the 87GB catalog in the North (Gregory and Condon et al. 1991, ApJ, 75, 1011, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/14">CDS Catalog VIII/14</a>) and the PMN catalogs (Griffith and Wright 1993, AJ, 105, 1666, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/38">CDS Catalog VIII/38</a>, available at the HEASARC as the PMN table) in the South." This table was updated by the HEASARC in July 2015 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VIII/15">CDS Catalog VIII/15</a> file pkscat90.dat, replacing a version based on the original (version 1) PKSCAT90, which was created in 1995. It was further updated in September 2015 as noted in the "Version 1.01 Modifications" section above. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pds1p4ghz
- Title:
- Phoenix Deep Survey 1.4-GHz Catalog
- Short Name:
- PDS1P4GHZ
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- 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 April 2018. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pdsoid
- Title:
- Phoenix Deep Survey Optical and Near-Infrared Counterparts Catalog
- Short Name:
- PDSOID
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Using a deep Australia Telescope Compact Array (ATCA) radio survey covering an area of ~3 deg<sup>2</sup> to a 4-sigma sensitivity of >= 100 microJy (uJy) 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 1<sup>h</sup> 14<sup>m</sup> 12.16<sup>s</sup>, -45<sup>o</sup> 44' 08.0" (Galactic latitude of -71<sup>o</sup>), 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 m<sub>R</sub> = 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 A<sub>V</sub> = 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 H<sub>0</sub> of 50 km s<sup>-1</sup> Mpc<sup>-1</sup> and a deceleration parameter q<sub>0</sub> 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 .
- ID:
- ivo://nasa.heasarc/pdsoid2
- Title:
- Phoenix Deep Survey Optical and Near-Infrared Counterparts Catalog 2
- Short Name:
- PDSOID2
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Phoenix Deep Survey (PDS) is a multi-wavelength galaxy survey based on deep 1.4-GHz radio imaging. The revised version of the radio source catalog was published by Hopkins et al. (2003). The primary goal of the PDS is to investigate the properties of star formation in galaxies and to trace the evolution in those properties to a redshift z = 1, covering a significant fraction of the age of the universe. By compiling a sample of star-forming galaxies based on selection at radio wavelengths, Sullivan et al. (2004, the reference paper for this present catalog) eliminate possible biases due to dust obscuration, a significant issue when selecting objects at optical and ultraviolet wavelengths. In this study, they present the catalogs and results of deep optical (UBVRI) and near-infrared (K<sub>s</sub>) imaging of the deepest region of the existing decimetric radio imagery. The observations and data processing are summarized and the construction of the optical source catalogs described in their paper, together with the details of the identification of candidate optical counterparts to the radio catalogs. Based on their UBVRIK<sub>s</sub> imaging, photometric redshift estimates for the optical counterparts to the radio detections are explored. Two pointings (labeled 7 and 3 in Table 1 of the reference paper) were observed in BVRi, and one (pointing 11 in ibid.) in BVi on the nights of 2001 August 13 and 14, with the WFI camera on the Anglo-Australian Telescope (AAT). The same three pointings were also observed in U with the Mosaic-II camera on the Cerro Tololo Inter-American Observatory (CTIO) 4-m Blanco telescope on 2002 September 3. Finally, four of the PDS fields (2, 3, 6, 7) were observed in U with the WFI on the European Southern Observatory (ESO) 2.2-m telescope on the night of 2001 August 18. The NIR imaging data come from the Hawaii HgCdTe 1024 x 1024 pixel array SoFI camera on the 3.6-m ESO New Technology Telescope (NTT). The field of view was 4.9' x 4.9' with a pixel scale of 0.29". Nine contiguous pointings, in a 3 x 3 pattern, were observed over the deepest region of the PDS (a sub-region of pointing 7; see Fig. 1 of the reference paper), during 2000 October 10 and October 11. Throughout this study, the authors assume an Omega<sub>Lambda</sub> = 0.7, Omega<sub>M</sub> = 0.3, h = 0.70 (where H<sub>0</sub> = 100 h km s<sup>-1</sup> Mpc<sup>-1</sup>) cosmology. This table was created by the HEASARC in June 2013 based on an electronic version of Table 6 from the reference paper, which details the photometric (optical and near-infrared) properties and redshifts of 778 radio sources in the PDS, which was obtained from the CDS web site (their catalog J/ApJS/155/1 file table6.dat). The HEASARC has changed the name prefixes of the sources in this table from 'PDS' (Phoenix Deep Survey) to 'PDF' (Phoenix Deep Field) as recommended by the CDS Dictionary of Astronomical Nomenclature. Three duplicate entries were removed from the catalog in June 2019. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pacobscat
- Title:
- Planck-ATCA Co-eval Observations (PACO) Project Bright Sample Catalog
- Short Name:
- PACOBSCAT
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Planck Australia Telescope Compact Array (Planck-ATCA) Co-eval Observations (PACO) have provided flux density measurements of well-defined samples of Australia Telescope 20-GHz (AT20G) radio sources at frequencies below and overlapping with Planck frequency bands, almost simultaneously with Planck observations. The authors have observed with the ATCA a total of 482 sources in the frequency range between 4.5 and 40 GHz in the period between 2009 July and 2010 August. Several sources were observed more than once. In their paper, the authors present the aims of the project, the selection criteria, and the observation and data reduction procedures. They also discuss the data in total intensity for a complete sample of 189 sources with 20-GHz flux densities > 500 mJy, Galactic latitude |b| > 5 degrees and Declination < -30 degrees, and some statistical analysis of the spectral behavior and variability of this sample, referred to as the 'bright PACO sample'. Finally, the authors discuss how these data could be used to transfer absolute calibrations to ground-based telescopes using the cosmic microwave background dipole calibrated flux densities measured by the Planck satellite, and they provide some test fluxes on bright calibrators. This table contains the catalog of 1004 observations of 180 of the 189 sources that comprise the 'bright PACO sample'. Thus, each row in this table corresponds to a specific observation of a source, and there can be several rows for any source, corresponding to different observations. The ATCA observations were made in 6 2-GHz wide observing bands: 4732 - 6780 MHz, 8232 - 10280 MHz, 17232 - 19280 MHz, 23232 - 25280 MHz, 32232 - 34280 MHz and 38232 - 40280 MHz. In order to properly define the detailed source spectral behavior, the authors have split each 2-GHz band into 4 x 512 MHz sub-bands, and calibrated each sub-band independently. Thus, for each observation, the flux density at 24 frequencies is given. The frequency identifier in the flux density appears (at least to this HEASARC scientist) to be the lower frequency of the sub-band rather than its central frequency. In order to provide the easiest way to extrapolate the observed counts or model predictions from one frequency to another, the authors have modeled the observed source spectra. As their observations covered a wide frequency range from 4.5 to 40 GHz over which a single power law is not enough to describe the spectral behavior of the sources, they studied the spectra of the 174 point-like sources in this sample by fitting the observed data with a double power law of the form S<sub>nu</sub> = S<sub>0</sub>/[(nu/nu<sub>0</sub>)<sup>-a</sup> + (nu/nu<sub>0</sub>)<sup>-b</sup>], where nu is the frequency, S<sub>nu</sub> is the flux density in Jy, and S<sub>0</sub>, nu<sub>0</sub>, a and b are free parameters. The authors considered only those sources for which they had at least four data points for each of the 2 x 2 GHz bands considered. Full details of the fitting procedure are given in Section 3.1 of the reference paper. This table was created by the HEASARC in January 2014 based on the machine-readable version of Table S1 from the reference paper which was obtained from the CDS (their catalog J/MNRAS/415/1597 file table1.dat). This is a service provided by NASA HEASARC .