Aravena, M.Decarli, R.Walter, F.Bouwens, R.Oesch, P.A.Carilli, C.L.Bauer, F.E.Cunha, E. DaDaddi, E.Gónzalez-López, J.Ivison, R.J.Riechers, D.A.Smail, I.Swinbank, A.M.Weiss, A.Anguita, T.Bacon, R.Bell, E.Bertoldi, F.Cortes, P.Cox, P.Hodge, J.Ibar, E.Inami, H.Infante, L.Karim, A.Magnelli, B.Ota, K.Popping, G.Van Der, Werf P.Wagg, J.Fudamoto, Y.2023-08-212023-08-212016-12Astrophysical Journal. Open Access. Volume 833, Issue 1. 10 December 2016. Article number 710004-637Xhttps://repositorio.unab.cl/xmlui/handle/ria/52687Indexación: ScopusWe present a search for [C II] line and dust continuum emission from optical dropout galaxies at z > 6 using ASPECS, our Atacama Large Millimeter submillimeter Array Spectroscopic Survey in the Hubble Ultra-deep Field (UDF). Our observations, which cover the frequency range of 212–272 GHz, encompass approximately the range of 6 < z < 8 for [C II] line emission and reach a limiting luminosity of L[C II] ∼ (1.6–2.5) × 108 Le. We identify 14 [C II] line emitting candidates in this redshift range with significances >4.5σ, two of which correspond to blind detections with no optical counterparts. At this significance level, our statistical analysis shows that about 60% of our candidates are expected to be spurious. For one of our blindly selected [C II] line candidates, we tentatively detect the CO(6-5) line in our parallel 3 mm line scan. None of the line candidates are individually detected in the 1.2 mm continuum. A stack of all [C II] candidates results in a tentative detection with S1.2 mm = 14 ± 5 μJy. This implies a dust-obscured star-formation rate (SFR) of (3 ± 1) Me yr−1 . We find that the two highest-SFR objects have candidate [C II] lines with luminosities that are consistent with the low-redshift L[C II] versus SFR relation. The other candidates have significantly higher [C II] luminosities than expected from their UV-based SFR. At the current sensitivity, it is unclear whether the majority of these sources are intrinsically bright [C II] emitters, or spurious sources. If only one of our line candidates was real (a scenario greatly favored by our statistical analysis), we find a source density for [C II] emitters at 6 < z < 8 that is significantly higher than predicted by current models and some extrapolations from galaxies in the local universe.enGalaxies: EvolutionGalaxies: High-RedshiftGalaxies: ISMGalaxies: Star FormationInstrumentation: InterferometersSubmillimeter: GalaxiesArtículoAtribution 4.0 International (CC BY 4.0)10.3847/1538-4357/833/1/71