VLA ELAIS N1, N2, N3 Fields 20-cm Source Catalog

VLA ELAIS N1, N2, N3 Fields 20-cm Source Catalog VLAEN20CM ivo://nasa.heasarc/vlaen20cm NASA/GSFC HEASARC Ciliegi et al. 2026-04-03 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source The authors have used the Very Large Array (VLA) in C configuration to carry out a sensitive 20-cm radio survey of regions of the sky that have been surveyed in the far-infrared (FIR) over the wavelength range 5 -200 microns (µm) with ISO (Infrared Space Observatory) as part of the European Large-Area ISO Survey (ELAIS). As usual in surveys based on a relatively small number of overlapping VLA pointings, the flux limit varies over the area surveyed: from a 5-sigma limit of 0.135 mJy over an area of 0.12 deg2 to 1.15 mJy or better over the whole region covered of 4.22 deg2. In their paper, the authors present the complete radio catalog of 867 sources, 428 of which form a complete sample in the flux range 0.2 - 1.0 mJy. These regions of the sky have previously been surveyed to shallower flux limits at 20 cm with the VLA as part of the VLA D-configuration NVSS (full width at half-maximum, FWHM = 45arcseconds) and VLA-B configuration FIRST (FWHM = 5 arcseconds) surveys. This whole survey has a nominal 5-sigma flux limit a factor of 2 below that of the NVSS; 3.4 deg2 of the survey reaches the nominal flux limit of the FIRST survey and 1.5 deg2 reaches 0.25 mJy, a factor of 4 below the nominal FIRST survey limit. In addition, this survey is at a resolution intermediate between the two surveys and thus is well suited for a comparison of the reliability and resolution-dependent surface brightness effects that affect interferometric radio surveys. The authors have carried out a detailed comparison of their survey and these two independent surveys in order to assess the reliability and completeness of each. Considering the whole sample, they found that to the 5-sigma nominal limits of 2.3 and 1.0 mJy, respectively, the NVSS and FIRST surveys have a completeness of 96+2-3 and 89+2-3 % and a reliability of 99+1-2 and 94+2-2 %. The radio observations were obtained of three ISO ELAIS survey regions in the Northern celestial hemisphere (N1 1610+5430, N2 1636+4115 and N3 1429+3306) (see Table 1 of the reference paper for the details of the fields and the individual pointings). The observations are made with the Very Large Array (VLA) radio telescope at 1.4 GHz (20 cm) in the VLA C configuration (maximum baseline 3.4 km) with an angular resolution (FWHM) of ~15 arcseconds. The aim of these VLA observations was to obtain uniform coverage of the ELAIS regions with an rms noise limit of ~50 microJansky (µJy). This table contains the 921 components of 867 total sources detected at a level of >= 5 sigma (44 of which are multiple component sources as defined in Section 4.3 of the reference paper) over a total area of 4.222 deg2. There are also entries describing the properties of the total sources for the 44 multi-component sources (for which the positions have been computed as the flux-weighted average positions of their components), and thus this catalog contains 965 (921 + 44) entries. To filter out the latter, component_id values != 'T' should be selected when searching this table. This table was originally ingested by the HEASARC in August 2012, based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/302/222">CDS Catalog J/MNRAS/302/222</a> file table3.dat. It was last updated in September 2013 to remove a duplicate entry for the source ELAISR J142743+331323. This is a service provided by NASA HEASARC . 1999MNRAS.302..222C https://heasarc.gsfc.nasa.gov/W3Browse/all/vlaen20cm.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=vlaen20cm& GET text/xml 180 99999 true 217.20736292 32.63779167 0.0833333333333333 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=vlaen20cm GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_vlaen20cm&Action=More+Options&Action=Parameter+Search&ConeAdd=1 RADIO CATALOG 0.0833333333333333 Radio public vlaen20cm VLA ELAIS N1, N2, N3 Fields 20-cm Source Catalog dec_error RMS Uncertainty in Declination arcsec stat.error;pos.eq.dec;meta.main double nullable major_axis_error RMS Uncertainty in Major Axis arcsec stat.error;phys.angSize.smajAxis double nullable snr Signal-to-Noise Ratio stat.snr;phot.flux.density;em.radio.750-1500MHz double nullable minor_axis FWHM of the Minor Axis arcsec phys.angSize.sminAxis double nullable "__x_ra_dec" System unit vector column double nullable dec Declination degree pos.eq.dec;meta.main double nullable "__y_ra_dec" System unit vector column double nullable lii Galactic Longitude degree pos.galactic.lon double nullable "__row" System index column char nullable major_axis FWHM of the Major Axis arcsec phys.angSize.smajAxis double nullable component_id Component Identifier [ABCD], [T]=Total Source meta.code.multip char nullable minor_axis_error RMS Uncertainty in Minor Axis arcsec stat.error;phys.angSize.sminAxis double nullable position_angle_error RMS Uncertainty in Position Angle degree stat.error;pos.posAng double nullable position_angle Position Angle of the Major Axis Measured East to North degree pos.posAng double nullable flux_20_cm Peak Flux Density at 1.4GHz mJy/beam phot.flux.density;em.radio.750-1500MHz double nullable "__z_ra_dec" System unit vector column double nullable int_flux_20_cm_error RMS Uncertainty in Total Flux Density at 1.4GHz mJy stat.error;phot.flux.density;em.radio.750-1500MHz double nullable flux_20_cm_error RMS Uncertainty in Peak Flux Density at 1.4GHz mJy/beam stat.error;phot.flux.density;em.radio.750-1500MHz double nullable y_pixel Y Position (1 pixel = 3 arcsec) pixel pos.cartesian.y;instr.pixel double nullable ra_error RMS Uncertainty in Right Ascension arcsec stat.error;pos.eq.ra;meta.main double nullable bii Galactic Latitude degree pos.galactic.lat double nullable int_flux_20_cm Total Flux Density at 1.4GHz mJy phot.flux.density;em.radio.750-1500MHz double nullable elais_field Field Designation (N1, N2, N3) meta.id;obs.field char nullable x_pixel X Position (1 pixel = 3 arcsec) pixel pos.cartesian.x;instr.pixel double nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable off_axis Off-Axis Value in the VLA Map arcmin instr.offset double nullable name Source Designation, ELAISR JHHMMSS+DDMMSSA meta.id;meta.main char nullable