The ALPINE-ALMA [C II] Survey: [C II] 158 μm Emission Line Luminosity Functions at z ∼ 4-6

Yan, LinLinYanSajina, A.A.SajinaLoiacono, F.F.LoiaconoLagache, G.G.LagacheBéthermin, M.M.BétherminFaisst, A.A.FaisstGinolfi, M.M.GinolfiFèvre, O. LeO. LeFèvreGRUPPIONI, CarlottaCarlottaGRUPPIONICapak, P. L.P. L.CapakCassata, P.P.CassataSchaerer, D.D.SchaererSilverman, J. D.J. D.SilvermanBARDELLI, SandroSandroBARDELLIDessauges-Zavadsky, M.M.Dessauges-ZavadskyCimatti, A.A.CimattiHathi, N. P.N. P.HathiLemaux, B. C.B. C.LemauxIbar, E.E.IbarJones, G. C.G. C.JonesKoekemoer, Anton M.Anton M.KoekemoerOesch, P. A.P. A.OeschTalia, M.M.TaliaPozzi, F.F.PozziRiechers, D. A.D. A.RiechersTasca, L. A. M.L. A. M.TascaToft, SuneSuneToftVALLINI, LiviaLiviaVALLINIVERGANI, DANIELADANIELAVERGANIZamorani, G.G.ZamoraniZUCCA, ElenaElenaZUCCA2025-02-282025-02-2820200004-637Xhttp://hdl.handle.net/20.500.12386/36339We present the [C II] 158 μm line luminosity functions (LFs) at z ∼ 4-6 using the ALMA observations of 118 sources, which are selected to have UV luminosity M1500Å < -20.2 and optical spectroscopic redshifts in COSMOS and ECDF-S. Of the 118 targets, 75 have significant [C II] detections and 43 are upper limits. This is by far the largest sample of [C II] detections, which allows us to set constraints on the volume density of [C II] emitters at z ∼ 4-6. But because this is a UV-selected sample, we are missing [C II]-bright but UV-faint sources, making our constraints strict lower limits. Our derived LFs are statistically consistent with the z ∼ 0 [C II] LF at 108.25-109.75L⊙. We compare our results with the upper limits of the [C II] LF derived from serendipitous sources in the ALPINE maps. We also infer the [C II] LFs based on published far-IR and CO LFs at z ∼ 4-6. Combining our robust lower limits with these additional estimates, we set further constraints on the true number density of [C II] emitters at z ∼ 4-6. These additional LF estimates are largely above our LF at L[CII] > 109L⊙, suggesting that UV-faint but [C II]-bright sources likely make significant contributions to the [C II] emitter volume density. When we include all the LF estimates, we find that available model predictions underestimate the number densities of [C II] emitters at z ∼ 4-6. Finally, we set a constraint on the molecular gas mass density at z ∼ 4-6, with ρmol ∼ (2-7) × 107M⊙ Mpc-3. This is broadly consistent with previous studies.STAMPAenThe ALPINE-ALMA [C II] Survey: [C II] 158 μm Emission Line Luminosity Functions at z ∼ 4-6Article10.3847/1538-4357/abc41c2-s2.0-85098892183https://iopscience.iop.org/article/10.3847/1538-4357/abc41chttps://api.elsevier.com/content/abstract/scopus_id/850988921832020ApJ...905..147YFIS/05 - ASTRONOMIA E ASTROFISICA