J/A+A/694/A261ivo://CDS.VizieR/J/A+A/694/A261doi:10.26093/cds/vizier/bc-np/lcgbCDSGao F.Wang T.Wang Y.2026-07-03T06:36:25Z2025-05-30T15:06:11ZCDS support team

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

cds-question@unistra.frradio-galaxiesinfrared-photometryvisible-astronomymillimeter-astronomyphotometrysubmillimeter-astronomygalaxy-classification-systemsRadio observations provide a powerful tool to constrain the assembly of galaxies over cosmic time. Recent deep and wide radio continuum surveys have improved significantly our understanding on radio emission properties of active galactic nuclei (AGNs) and star-forming galaxies (SFGs) across 0<z<4. This allows us to derive an empirical model of the radio continuum emission of galaxies based on their star formation rates and the probability of hosting an radio AGN. Here we verify how well this empirical model can reproduce the extragalactic radio background (ERB), which can provide new insights into the contribution to the ERB from galaxies of different masses and redshifts.We make use of the Empirical Galaxy Generator (EGG) to generate a near-infrared (NIR)-selected, flux-limited multi-wavelength catalog to mimic real observations. Then we assign radio continuum flux densities to galaxies based on their star formation rates and the probability of hosting a radio-AGN of specific 1.4GHz luminosity. We also apply special treatments to reproduce the clustering signal of radio AGNs.Our empirical model successfully recovers the observed 1.4GHz radio luminosity functions (RLFs) of both AGN and SFG populations, as well as the differential number counts at various radio bands. The uniqueness of this approach also allows us to directly link radio flux densities of galaxies to other properties, including redshifts, stellar masses, and magnitudes at various photometric bands. We find that roughly half of the radio continuum sources to be detected by the Square Kilometer Array (SKA) at z~4-6 will be too faint to be detected in the optical survey (r~27.5) carried out by Rubin observatory.Unlike previous studies which utilized (extrapolations of) RLFs to reproduce ERB, our work starts from a simulated galaxy catalog with realistic physical properties. It has the potential to simultaneously, and self-consistently reproduce physical properties of galaxies across a wide range of wavelengths, from optical, NIR, far-infrared (FIR) to radio wavelengths. Our empirical model can shed light on the contribution of different galaxies to the extragalactic background light, and greatly facilitates designing future multiwavelength galaxy surveys.2025A&A...694A.261Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/694/A261CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/694/A261https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/694/A261http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/694/A261https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/694/A261https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/694/A261http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/694/A261GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/694/A261/catalog (Mock catalog with multi-wavelength information and radio properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/694/A261/catalog?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/694/A261/catalog?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/694/A261/catalog?GETtext/xml+votable180.050000true1.660930632420.371231103670.0055555555555555565/4522 6/17405 17407 18082 18094 19456-194579.939104750406538e-26 6.090060298487514e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/694/A261?format=asciiOpticalInfraredMillimeterRadiodefaultJ/A+A/694/A261/catalogMock catalog with multi-wavelength information and radio propertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDIdentification number generated by EGGmeta.id;meta.mainintRAJ2000[] Right Ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000)degpos.eq.dec;meta.mainindexedzRedshiftsrc.redshiftdoublelogMasslog stellar masslog(solMass)phys.massdoubleSFRstar formation ratessolMass/yrphys.SFRdoublePassive[0/1] 1 if passive galaxiesmeta.codeintLIRInfrared luminositysolLumphys.luminosity;em.IRdoubleFuSDSS u band flux densityJyphot.mag;em.opt.UdoubleFgSDSS g band flux densityJyphot.mag;em.opt.BdoubleFrSDSS r band flux densityJyphot.mag;em.opt.RdoubleFiSDSS i band flux densityJyphot.mag;em.opt.IdoubleFzSDSS z band flux densityJyphot.mag;em.opt.IdoubleFF606WHST F606W band flux densityJyphot.mag;em.opt.RdoubleFF775WHST F775W band flux densityJyphot.mag;em.opt.IdoubleFF814WHST F814W band flux densityJyphot.mag;em.opt.IdoubleFF140WJWST F140W band flux densityJyphot.flux;em.UVdoubleFF160WJWST F160W band flux densityJyphot.flux;em.UVdoubleFF444WJWST F444W band flux densityJyphot.flux;em.UVdoubleFKsWIRCAM Ks band flux densityJyphot.mag;em.IR.KdoubleFIRAC1Spitzer 3.6um band flux densityJyphot.mag;em.IR.3-4umdoubleFIRAC2Spitzer 4.5um band flux densityJyphot.mag;em.IR.4-8umdoubleFIRAC3Spitzer 5um band flux densityJyphot.flux.density;em.IR.4-8umdoubleFIRAC4Spitzer 8um band flux densityJyphot.flux.density;em.IR.8-15umdoubleFMIPSSpitzer mips 24umJyphot.flux.density;em.IR.15-30umdoubleFS250Herschel SPIRE 250umJyphot.flux.density;em.mm.750-1500GHzdoubleFS350Herschel SPIRE 350umJyphot.flux.density;em.mm.750-1500GHzdoubleFS500Herschel SPIRE 500umJyphot.flux.density;em.mm.400-750GHzdoubleRANdeg? New Right Ascension for galaxies>10^10^M_{sun}_ (1)degpos.eq.ranullableDENdeg? New Declination for galaxies>10^10^M_{sun}_ (1)degpos.eq.decnullableAGN[1]? 1 if radio AGNmeta.codeintnullableL1.4GHzRest-frame 1.4GHz luminosityW/Hzphys.luminosity;em.radiodoubleqirRatio between IR luminosity and rest-frame 1.4GHz radio luminosity (qIR) value for non-AGNsphot.flux;arith.ratiodoublealphalowSpectral slope at 150 and 350MHz (2)spect.indexdoublealphahighSpectral slope at 1.4, 3, 10 and 15GHz (2)spect.indexdoubleF150MHz150MHz flux densityJyphot.flux.density;em.radio.100-200MHzdoubleF350MHz350MHz flux densityJyphot.flux.density;em.radio.200-400MHzdoubleF1.4GHz1.4GHz flux densityJyphot.flux.density;em.radio.750-1500MHzdoubleF3GHz3GHz flux densityJyphot.flux.density;em.radio.1500-3000MHzdoubleF10GHz10GHz flux densityJyphot.flux.density;em.radio.6-12GHzdoubleF15GHz15GHz flux densityJyphot.flux.density;em.radio.12-30GHzdoubletheta? 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