J/MNRAS/473/4523ivo://CDS.VizieR/J/MNRAS/473/4523doi:10.26093/cds/vizier.74734523CDSWeston S.D.Seymour N.Gulyaev S.Norris R.P.Banfield J.Vaccari M.,Hopkins A.M.Franzen T.M.O.2024-08-17T20:21:43Z2021-02-10T15:11:41ZCDS support team

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

cds-question@unistra.frsurveysradio-galaxiesCross-identifying complex radio sources with optical or infrared (IR) counterparts in surveys such as the Australia Telescope Large Area Survey (ATLAS) has traditionally been performed manually. However, with new surveys from the Australian Square Kilometre Array Pathfinder detecting many tens of millions of radio sources, such an approach is no longer feasible. This paper presents new software (LRPY - Likelihood Ratio in PYthon) to automate the process of cross-identifying radio sources with catalogues at other wavelengths. lrpy implements the likelihood ratio (LR) technique with a modification to account for two galaxies contributing to a sole measured radio component. We demonstrate lrpy by applying it to ATLAS DR3 and a Spitzer-based multiwavelength fusion catalogue, identifying 3848 matched sources via our LR-based selection criteria. A subset of 1987 sources have flux density values for all IRAC bands which allow us to use criteria to distinguish between active galactic nuclei (AGNs) and star-forming galaxies (SFG). We find that 936 radio sources (~=47 per cent) meet both of the Lacy and Stern AGN selection criteria. Of the matched sources, 295 have spectroscopic redshifts and we examine the radio to IR flux ratio versus redshift, proposing an AGN selection criterion below the Elvis radio-loud AGN limit for this dataset. Taking the union of all three AGNs selection criteria we identify 956 as AGNs (~= 48 per cent). From this dataset, we find a decreasing fraction of AGNs with lower radio flux densities consistent with other results in the literature.2018MNRAS.473.4523Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/473/4523CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/453/4020 : ATLAS 1.4GHz Data Release 3 (Franzen+, 2015)http://mattiavaccari.net/df : Spitzer Data Fusion,https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/473/4523https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/473/4523http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/473/4523https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/473/4523https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/473/4523http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/473/4523GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/473/4523/table7 (ATLAS/FUSION SWIRE cross-identification catalogue for the CDFS field)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/473/4523/table7?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/473/4523/table7?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/473/4523/table7?GETtext/xml+votable180.050000true53.986-28.78010.005555555555555556Cone search capability for table J/MNRAS/473/4523/table8 (ATLAS/FUSION SWIRE cross-identification catalogue for the ELAIS-S1 field)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/473/4523/table8?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/473/4523/table8?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/473/4523/table8?GETtext/xml+votable180.050000true9.0696-43.15960.0055555555555555565/8983 8989 6/35385 35387-35388 35390 35473 35475-35476 35931 35953 361069.276497240453405e-25 5.517906024225661e-20https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/473/4523?format=asciiRadiodefaultJ/MNRAS/473/4523/table7ATLAS/FUSION SWIRE cross-identification catalogue for the CDFS fieldrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintATLASATLAS DR3 Identification number of the radio sourcemeta.id;meta.maincharRAJ2000Radio source right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Radio source declination (J2000)degpos.eq.dec;meta.mainSp1.4GHz? Peak radio flux densities at 1.4GHzmJy/beamphot.flux.density;em.radio.750-1500MHzdoublenullableSi1.4GHz? Integrated radio flux densities at 1.4GHzmJyphot.flux.density;em.radio.750-1500MHzdoublenullableSWIREFusion Identification number, swire_index_spitzermeta.idintRAIdegIR candidate right ascension (J2000)degpos.eq.raDEIdegIR candidate declination (J2000)degpos.eq.decS3.6umIR flux density at 3.6umuJyphot.mag;em.IR.3-4umdoublee_S3.6umIR flux density uncertainty at 3.6umuJystat.errorfloatlogLRLog10 of likelihood ratio of the IR candidatestat.likelihoodfloatRelReliability of the IR candidatemeta.code.qualfloatJ/MNRAS/473/4523/table8ATLAS/FUSION SWIRE cross-identification catalogue for the ELAIS-S1 fieldrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintATLASATLAS DR3 Identification number of the radio sourcemeta.id;meta.maincharRAJ2000Radio source right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Radio source declination (J2000)degpos.eq.dec;meta.mainSp1.4GHz? Peak radio flux densities at 1.4GHzmJy/beamphot.flux.density;em.radio.750-1500MHzdoublenullableSi1.4GHz? Integrated radio flux densities at 1.4GHzmJyphot.flux.density;em.radio.750-1500MHzdoublenullableSWIREFusion Identification number, swire_index_spitzermeta.idintRAIdegIR candidate right ascension (J2000)degpos.eq.raDEIdegIR candidate declination (J2000)degpos.eq.decS3.6umIR flux density at 3.6umuJyphot.mag;em.IR.3-4umdoublee_S3.6umIR flux density uncertainty at 3.6umuJystat.errorfloatlogLRLog10 of likelihood ratio of the IR candidatestat.likelihoodfloatRelReliability of the IR candidatemeta.code.qualfloat