- ID:
- ivo://CDS.VizieR/J/MNRAS/441/2555
- Title:
- ATLAS 1.4GHz Data Release 2
- Short Name:
- J/MNRAS/441/2555
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first of two papers describing the second data release (DR2) of the Australia Telescope Large Area Survey at 1.4GHz, which comprises deep wide-field observations in total intensity, linear polarization, and circular polarization over the Chandra Deep Field-South and European Large Area Infrared Space Observatory Survey-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 multipointing images are 30{mu}Jy/beam at approximately 12"x6" resolution over a combined area of 6.4deg^2^. In this paper we present detailed descriptions of our 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. We present the DR2 images and catalogues of components (discrete regions of radio emission) and sources (groups of physically associated radio components). We describe new analytic methods to account for resolution bias and Eddington bias when constructing differential number counts of radio components.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/4020
- Title:
- ATLAS 1.4GHz Data Release 3
- Short Name:
- J/MNRAS/453/4020
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the third data release from the Australia Telescope Large Area Survey. These data combine the observations at 1.4GHz before and after upgrades to the Australia Telescope Compact Array reaching a sensitivity of 14{mu}Jy/beam in 3.6 deg^2^ over the Chandra Deep Field South (CDFS) and of 17{mu}Jy/beam in 2.7 deg^2^ over the European Large Area ISO Survey South 1 (ELAIS-S1). We used a variety of array configurations to maximize the uv coverage resulting in a resolution of 16 by 7-arcsec in CDFS and of 12 by 8-arcsec in ELAIS-S1. After correcting for peak bias and bandwidth smearing, we find a total of 3034 radio source components above 5{sigma} in CDFS, of which 514 (17 per cent) are considered to be extended. The number of components detected above 5{sigma} in ELAIS-S1 is 2084, of which 392 (19 per cent) are classified as extended. The catalogues include reliable spectral indices ({Delta}{alpha}<0.2) between 1.40 and 1.71GHz for ~350 of the brightest components.
- ID:
- ivo://CDS.VizieR/J/A+A/544/A38
- Title:
- ATLAS 2.3GHz observations of ELAIS-S1 and CDF-S
- Short Name:
- J/A+A/544/A38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Australia Telescope Large Area Survey (ATLAS) aims to image a 7deg^2^ region centred on the European Large Area ISO Survey - South 1 (ELAIS-S1) field and the Chandra Deep Field South (CDF-S) at 1.4GHz with high sensitivity (up to {sigma}~10uJy) to study the evolution of star-forming galaxies (SFGs) and Active Galactic Nuclei (AGN) over a wide range of cosmic time. We present here ancillary radio observations at a frequency of 2.3GHz obtained with the Australia Telescope Compact Array (ATCA). The main goal of this is to study the radio spectra of an unprecedented large sample of sources (~2000 observed, ~600 detected in both frequencies).
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/2342
- Title:
- ATLAS 5.5GHz survey of Chandra Deep Field South
- Short Name:
- J/MNRAS/426/2342
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- 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. We have observed the extended Chandra Deep Field South at 5.5GHz using a mosaic of 42 pointings with the Australia Telescope Compact Array. Our image reaches an almost uniform sensitivity of ~12Jy rms over 0.25deg^2^ with a restoring beam of 4.9"x2.0", making ATLAS 5.5GHz survey one of the deepest 6cm surveys to date. We present the 5.5GHz catalogue and source counts from this field. We take advantage of the large amount of ancillary data in this field to study the 1.4 to 5.5GHz spectral indices of the sub-mJy population.
- ID:
- ivo://CDS.VizieR/J/ApJS/211/29
- Title:
- Atlas of HI absorption toward HII regions in SGPS I
- Short Name:
- J/ApJS/211/29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a complete catalog of H I emission and absorption spectrum pairs, toward H II regions, detectable within the boundaries of the Southern Galactic Plane Survey (SGPS I), a total of 252 regions. The catalog is presented in graphical, numerical, and summary formats. We demonstrate an application of this new data set through an investigation of the locus of the Near 3kpc Arm.
- ID:
- ivo://CDS.VizieR/J/AJ/135/1276
- Title:
- ATLAS radio observations of ELAIS-S1
- Short Name:
- J/AJ/135/1276
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have conducted sensitive (1{sigma}<30uJy) 1.4GHz radio observations with the Australia Telescope Compact Array of a field largely coincident with infrared observations of the Spitzer Wide-Area Extragalactic Survey (SWIRE, 2003PASP..115..897L). The field is centered on the European Large Area ISO Survey S1 region and has a total area of 3.9{deg}. We describe the observations and calibration, source extraction, and cross-matching to infrared sources. Two catalogs are presented: one of the radio components found in the image and another of radio sources with counterparts in the infrared and extracted from the literature. 1366 radio components were grouped into 1276 sources, 1183 of which were matched to infrared sources. We discover 31 radio sources with no infrared counterpart at all, adding to the class of Infrared-Faint Radio Sources.
- ID:
- ivo://CDS.VizieR/J/A+A/538/A120
- Title:
- A unified supernova catalogue
- Short Name:
- J/A+A/538/A120
- Date:
- 28 Feb 2022 07:37:53
- Publisher:
- CDS
- Description:
- A supernova catalogue containing data for 5526 extragalactic supernovae that were discovered up to 2010 December 31. It combines several catalogues that are currently available online in a consistent and traceable way. During the comparison of the catalogues inconsistent entries were identified and resolved where possible. Remaining inconsistencies are marked transparently and can be easily identified. Thus it is possible to select a high-quality sample in a most simple way. Where available, redshift-based distance estimates to the supernovae were replaced by journal-refereed distances.
- ID:
- ivo://CDS.VizieR/J/MNRAS/402/2403
- Title:
- Australia Telescope 20GHz Survey Catalog, AT20G
- Short Name:
- J/MNRAS/402/2403
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Australia Telescope 20GHz Survey (AT20G) is a blind radio survey carried out at 20GHz with the Australia Telescope Compact Array (ATCA) from 2004 to 2008, and covers the whole sky south of declination 0{deg}. 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 20GHz flux-density limit of 40mJy. All AT20G sources have total intensity and polarisation measured at 20GHz, and most sources south of declination -15{deg} also have near-simultaneous flux-density measurements at 5 and 8GHz. A total of 1559 sources were detected in polarised total intensity at one or more of the three frequencies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/426/3334
- Title:
- Australia Telescope Large Area Survey
- Short Name:
- J/MNRAS/426/3334
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Australia Telescope Large Area Survey (ATLAS) has surveyed 7 square degrees of sky around the Chandra Deep Field South and the European Large Area ISO Survey-South 1 fields at 1.4GHz. ATLAS aims to reach a uniform sensitivity of 10uJy/beam rms over the entire region with first data release currently reaching ~30uJy/beam rms. Here we present 466 new spectroscopic redshifts for radio sources in ATLAS as part of our optical follow-up programme. 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/762/16
- Title:
- Australia Telescope Low-brightness Survey (ATLBS)
- Short Name:
- J/ApJ/762/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Australia Telescope Low-brightness Survey (ATLBS) regions have been mosaic imaged at a radio frequency of 1.4GHz with 6" angular resolution and 72{mu}Jy/beam rms noise. The images (centered at RAJ2000=00:35:00, DEJ2000=-67:00:00 and RAJ2000=00:59:17, DEJ2000=-67:00:00) cover 8.42deg^2^ 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 4m CTIO Blanco telescope) were used to recognize multi-component sources and prepare a source list; the detection threshold was 0.38mJy in a low-resolution radio image made with beam FWHM of 50". Radio source counts in the flux density range 0.4-8.7mJy 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 1mJy the ATLBS counts are systematically lower than the previous estimates. Showing no evidence for an upturn down to 0.4mJy, 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.
