VLACOSXOID ivo://nasa.heasarc/vlacosxoid NASA/GSFC HEASARC Smolcic et al. 2026-10-02 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source In the reference paper, the authors study the composition of the faint radio population selected from the VLA-COSMOS 3-GHz Large Project, a radio continuum survey performed at 10-cm wavelength. The survey covers a 2.6 square degree area with a mean rms of ~2.3 µJy/beam (µJy/beam), cataloguing 10,830 sources above 5 sigma, and enclosing the full 2 square degree COSMOS field. By combining these radio data with optical, near-infrared (UltraVISTA), and mid-infrared (Spitzer/IRAC) data, as well as X-ray data (Chandra), the authors find counterparts to radio sources for ~93% of the total radio sample in the unmasked areas of the COSMOS field, i.e., those not affected by saturated or bright sources in the optical to near-IR (NIR) bands, reaching out to z ~ 6. They further classify the sources as star-forming galaxies or AGN based on various criteria, such as X-ray luminosity, observed mid-infrare (MIR) color, UV-far-infrared (FIR) spectral-energy distribution (SED), rest-frame near-ultraviolet (NUV)-optical color corrected for dust extinction, and radio-excess relative to that expected from the the hosts' star-formation rate. The authors separate the AGN into sub-samples dominated by low-to-moderate and moderate-to-high radiative luminosity AGN, i.e., candidates for high-redshift analogs to local low- and high-excitation emission line AGN, respectively. They study the fractional contributions of these sub-populations down to radio flux levels of ~11 uJy at 3 GHz (or ~20 uJy at 1.4 GHz assuming a spectral index of -0.7), and find that the dominant fraction at 1.4 GHz flux densities above ~200 uJy is constituted of low-to-moderate radiative luminosity AGN MLAGN). Below densities of ~100 uJy the fraction of star-forming galaxies (SFG) increases to ~60%, followed by the moderate-to-high radiative luminosity AGN (HLAGN) with ~20%, and MLAGN with ~20%. Based on this observational evidence, the authors extrapolate the fractions down to sensitivities of the Square Kilometer Array (SKA). Their estimates suggest that at the faint flux limits to be reached by the (Wide, Deep, and UltraDeep) SKA1 surveys, a selection based only on radio flux limits can provide a simple tool to efficiently identify samples highly (>75%) dominated by star-forming galaxies. This table contains the full list of 9,161 optical-MIR counterparts collected over the largest unmasked area accessible to each catalog, being 1.77, 1.73, and 2.35 square degrees for COSMOS2015, i-band, and IRAC catalogs, respectively. The catalog lists the counterpart IDs, properties, as well as the individual criteria used in this work to classify these radio sources. The authors note that complete, non-overlapping samples within a well defined, effective area of 1.77 square degrees (COSMOS2015 masked area flag_C15 = 0, can be formed by combining (i) HLAGN, MLAGN, and clean SFG samples, or, alternatively, (ii) the radio-excess and no-radio-excess samples. This table was created by the HEASARC in July 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/602/A2">CDS Catalog J/A+A/602/A2</a> file table1.dat, the VLA-COSMOS 3-GHz Large Project multiwavelength counterpart catalog. This is a service provided by NASA HEASARC . 2017A&A...602A...2S https://heasarc.gsfc.nasa.gov/W3Browse/all/vlacosxoid.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=vlacosxoid& GET text/xml 180 99999 true 150.519822 1.45231 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=vlacosxoid GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_vlacosxoid&Action=More+Options&Action=Parameter+Search&ConeAdd=1 RADIO CATALOG 0.0166666666666667 Infrared Radio public vlacosxoid VLA-COSMOS 3-GHz Large Project Multiwavelength Counterparts Cata source_number Sequential Identification Number for Each Source in the Catalog meta.id;meta.main int nullable ra Radio Source Right Ascension degree pos.eq.ra;meta.main double nullable dec Radio Source Declination degree pos.eq.dec;meta.main double nullable off_set Angular Distance Between the VLA Source and Its Counterpart arcsec pos.angDistance double nullable false_match_prob False-Match Probability stat.probability double nullable redshift Best Available Redshift src.redshift double nullable flux_3_ghz Total Integrated Flux Density at 3 GHz mJy phot.flux.density;em.radio.1500-3000MHz double nullable log_lum_3_ghz Radio Luminosity at 10 cm (3 GHz) log(W/Hz) phys.luminosity;em.radio.1500-3000MHz double nullable hl_agn_flag Boolean Flag [TF] for HLAGN meta.code;src.class char nullable cosmos2015_maskarea_flag Flag [0-8] for the Area of 1.77 Degree^2 meta.code short nullable ctrpart_catalog Counterpart Catalog meta.ref;meta.table char nullable sf_rate Star-Formation Rate from LTIRSF Solar_Mass/yr phys.SFR double nullable clean_sf_gal_flag Boolean Flag [TF] for No Radio-Excess SFG meta.code;src.class char nullable log_lum_tot_irsf 8-1000um Luminosity of the Host Galaxy log(Solar_Luminosity) phys.luminosity;em.IR double nullable lii Radio Source Galactic Longitude degree pos.galactic.lon double nullable ctrpart_ra Counterpart Right Ascension degree pos.eq.ra double nullable sed_agn_flag Boolean Flag [TF] for SED AGN meta.code;src.class char nullable ml_agn_flag Boolean Flag [TF] for MLAGN meta.code;src.class char nullable sf_gal_flag Boolean Flag [TF] for Star-Forming Galaxy meta.code;src.class char nullable xray_agn_flag Boolean Flag [TF] for X-Ray AGN meta.code;em.X-ray char nullable multi_component_flag Boolean Flag [01] Indicates Multiple Component Radio Source meta.code;src short nullable radio_excess_flag Boolean Flag [TF] for (3-Sigma) Radio-Excess meta.code;src.class char nullable quiescent_mlagn_flag Boolean Flag [TF] for Quiescent MLAGN meta.code;src.class char nullable mir_agn_flag Boolean Flag [TF] for Mid-Infrared AGN meta.code;em.IR char nullable ctrpart_source_number Identification of the Optical/MIR Counterpart meta.id.cross int nullable ctrpart_dec Counterpart Declination degree pos.eq.dec double nullable bii Radio Source Galactic Latitude degree pos.galactic.lat double nullable log_lum_1p4_ghz Radio Luminosity at 21 cm (1.4 GHz) log(W/Hz) phys.luminosity;em.radio.750-1500MHz double nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable