J/ApJ/762/16ivo://CDS.VizieR/J/ApJ/762/16doi:10.26093/cds/vizier.17620016CDSThorat K.Subrahmanyan R.Saripalli L.Ekers R.D.2014-10-22T17:45:43Z2014-10-09T08:15:37ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frradio-sourcessurveysThe 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.2013ApJ...762...16Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/762/16CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)J/ApJS/203/15 : Counterparts to 1.4GHz sources in ECDF-S (Bonzini+, 2012)J/ApJS/199/27 : The ATLBS Extended Source Sample (Saripalli+, 2012)J/MNRAS/402/2792 : 1388MHz ATLBS Low-Brightness Survey (Subrahmanyan+, 2010)J/AJ/135/2470 : Radio observations of the HDFS region. IV. (Huynh+, 2008)J/AJ/130/1373 : Radio observations of the HDFS region. II (Huynh+, 2005)J/AJ/125/465 : Phoenix Deep Survey 1.4-GHz microJy Catalog (Hopkins+, 2003)J/ApJ/533/611 : 1.4GHz survey in HDF region (Richards+, 2000)J/A+AS/58/1 : 1412 MHz catalogue of Westerbork survey. I. (Windhorst+, 1984)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/762/16https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/762/16http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/762/16https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/762/16https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/762/16http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/762/16GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/762/16/table2 (The Australia Telescope Low-brightness Survey (ATLBS) survey 1.4GHz source catalog)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/762/16/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/762/16/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/762/16/table2?GETtext/xml+votable180.050000true5.5965417-67.02411110.0055555555555555565/8355 8356 8358 8361 6/33430 33436 33441 33443 334529.276497240453405e-25 9.276497240453405e-25https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/762/16?format=asciiRadiodefaultJ/ApJ/762/16/table2The Australia Telescope Low-brightness Survey (ATLBS) survey 1.4GHz source catalogrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintATLBSSource name (JHHMM.m+DDMMa) (1)meta.id;meta.maincharRAJ2000[0/1] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[65/68] Degree of Declination (J2000)pos.eq.dec;meta.mainSint[0.3/290] Integrated flux density at 1.4GHzmJyphot.flux.density;em.radio.750-1500MHzfloatTypeSource type based on high resolution image (2)meta.code.classcharN[1/4]? Number of components for complex sourcesmeta.numberintnullableACatLink to other ATLBS catalogs (Saripalli+, 2012, J/ApJS/199/27 and Subrahmanyan+, 2010, J/MNRAS/402/2792)meta.numberintnullable