DELVECCHIO, IvanIvanDELVECCHIODaddi, E.E.DaddiSargent, M. T.M. T.SargentJarvis, M. J.M. J.JarvisElbaz, D.D.ElbazJin, S.S.JinLiu, D.D.LiuWhittam, I. H.I. H.WhittamAlgera, H.H.AlgeraCarraro, R.R.CarraroD'Eugenio, C.C.D'EugenioDelhaize, J.J.DelhaizeKalita, B. S.B. S.KalitaLeslie, S.S.LeslieMolnár, D. Cs.D. Cs.MolnárNovak, M.M.NovakPRANDONI, ISABELLAISABELLAPRANDONISmolčić, V.V.SmolčićAo, Y.Y.AoAravena, M.M.AravenaBournaud, F.F.BournaudCollier, J. D.J. D.CollierRandriamampandry, S. M.S. M.RandriamampandryRandriamanakoto, Z.Z.RandriamanakotoRodighiero, G.G.RodighieroSchober, J.J.SchoberWhite, S. V.S. V.WhiteZamorani, G.G.Zamorani2025-02-242025-02-2420210004-6361http://hdl.handle.net/20.500.12386/36174Over the past decade, several works have used the ratio between total (rest 8−1000 μm) infrared and radio (rest 1.4 GHz) luminosity in star-forming galaxies (q<SUB>IR</SUB>), often referred to as the infrared-radio correlation (IRRC), to calibrate the radio emission as a star formation rate (SFR) indicator. Previous studies constrained the evolution of q<SUB>IR</SUB> with redshift, finding a mild but significant decline that is yet to be understood. Here, for the first time, we calibrate q<SUB>IR</SUB> as a function of both stellar mass (M<SUB>⋆</SUB>) and redshift, starting from an M<SUB>⋆</SUB>-selected sample of > 400 000 star-forming galaxies in the COSMOS field, identified via (NUV − r)/(r − J) colours, at redshifts of 0.1 < z < 4.5. Within each (M<SUB>⋆</SUB>,z) bin, we stacked the deepest available infrared/sub-mm and radio images. We fit the stacked IR spectral energy distributions with typical star-forming galaxy and IR-AGN templates. We then carefully removed the radio AGN candidates via a recursive approach. We find that the IRRC evolves primarily with M<SUB>⋆</SUB>, with more massive galaxies displaying a systematically lower q<SUB>IR</SUB>. A secondary, weaker dependence on redshift is also observed. The best-fit analytical expression is the following: q<SUB>IR</SUB>(M<SUB>⋆</SUB>, z) = (2.646 ± 0.024) × (1 + z)<SUP>( − 0.023 ± 0.008)</SUP>-(0.148 ± 0.013) × (log M<SUB>⋆</SUB>/M<SUB>⊙</SUB> − 10). Adding the UV dust-uncorrected contribution to the IR as a proxy for the total SFR would further steepen the q<SUB>IR</SUB> dependence on M<SUB>⋆</SUB>. We interpret the apparent redshift decline reported in previous works as due to low-M<SUB>⋆</SUB> galaxies being progressively under-represented at high redshift, as a consequence of binning only in redshift and using either infrared or radio-detected samples. The lower IR/radio ratios seen in more massive galaxies are well described by their higher observed SFR surface densities. Our findings highlight the fact that using radio-synchrotron emission as a proxy for SFR requires novel M<SUB>⋆</SUB>-dependent recipes that will enable us to convert detections from future ultra-deep radio surveys into accurate SFR measurements down to low-M<SUB>⋆</SUB> galaxies with low SFR.STAMPAenArticle10.1051/0004-6361/2020396472-s2.0-85102921830https://www.aanda.org/articles/aa/full_html/2021/03/aa39647-20/aa39647-20.htmlhttp://arxiv.org/abs/2010.05510v22021A&A...647A.123DFIS/05 - ASTRONOMIA E ASTROFISICA