J/MNRAS/515/3126 REBELS. Dust Continuum Detections at z>6.5 (Inami+, 2022)
The ALMA REBELS Survey: Dust continuum detections at z > 6.5.
Inami H., Algera H., Schouws S., Sommovigo L., Bouwens R., Smit R.,
Stefanon M., Bowler R.A.A., Endsley R., Ferrara A., Oesch P., Stark D.,
Aravena M., Barrufet L., da Cunha E., Dayal P., De Looze I., Fudamoto Y.,
Gonzalez V., Graziani L., Hodge J.A., Hygate A.P.S., Nanayakkara T.,
Pallottini A., Riechers D. A., Schneider R., Topping M., van der Werf P.
<Mon. Not. R. Astron. Soc. 515, 3126-3143 (2022)>
=2022MNRAS.515.3126I 2022MNRAS.515.3126I (SIMBAD/NED BibCode)
ADC_Keywords: Infrared sources ; Galaxies, IR ; Galaxy catalogs ;
Photometry, infrared
Keywords: methods: observational - galaxies: evolution - galaxies: formation -
galaxies: high-redshift - galaxies: ISM - infrared: galaxies
Abstract:
We report 18 dust continuum detections ≥3.3σ at ∼88um and 158um
out of 49 ultraviolet(UV)-bright galaxies MUV←21.3mag at z>6.5,
observed by the Cycle-7 ALMA Large Program, REBELS and its pilot
programs. This has more than tripled the number of dust continuum
detections known at z>6.5. Out of these 18 detections, 12 are
reported for the first time as part of REBELS. In addition, 15 of the
dust continuum detected galaxies also show a [CII]158um emission line,
providing us with accurate redshifts. We anticipate more line emission
detections from six targets (including three continuum detected
targets) where observations are still ongoing. We estimate that all of
the sources have an infrared (IR) luminosity LIR in a range of
(3-8)x1011L☉, except for one with
LIR=1.5(+0.8/-0.5)x1012L☉. Their fraction of obscured star
formation is significant at ≳50%, despite being UV-selected galaxies.
Some of the dust continuum detected galaxies show spatial offsets
(∼0.5-1.5") between the rest-UV and far-IR emission peaks. These
separations could imply spatially decoupled phases of obscured and
unobscured star formation, but a higher spatial resolution observation
is required to confirm this. REBELS offers the best available
statistical constraints on obscured star formation in UV-luminous
galaxies at z>6.5.
Description:
The dust continuum flux measurements of the REBELS targets (the first
40 sources) and the pilot targets (the last nine sources) are
presented.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 127 53 Catalogue of the dust continuum fluxes of the
40 REBELS targets and the nine pilot targets
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- REBELS REBELS name (REBELS-NN)
12- 25 A14 --- ALMA ALMA source name
28- 30 A3 --- AName Alternative ALMA source name (4)
33- 38 F6.4 --- z Spectroscopic or photometric redshift
41- 44 A4 --- f_z [True ] Photometric redshift flag (3)
47- 52 F6.2 GHz Freq Observed frequency
55 A1 --- l_Flux Upper limit flag on continuum flux
58- 60 I3 uJy Flux Continuum flux (1)
63- 64 I2 uJy e_Flux ? Error on continuum flux
66- 69 F4.1 --- SNR ? Signal to noise ratio on continuum flux
72 A1 --- l_LIR Upper limit flag on infrared luminosity
75- 78 F4.1 10+11Lsun LIR ? Infrared luminosity (2)
81- 83 F3.1 10+11Lsun E_LIR ? Upper error on infrared luminosity
86- 88 F3.1 10+11Lsun e_LIR ? Lower error on infrared luminosity
91 A1 --- l_lFlux1 Upper limit flag on the first set of
continuum flux from literature
94- 98 F5.1 uJy lFlux1 ? The first set of continuum flux from
literature (4)
101-104 F4.1 uJy e_lFlux1 ? Error on the first set of continuum
flux from literature
107-109 A3 --- r_lFlux1 Reference for the first set of
continuum flux (4)
112-116 F5.1 uJy lFlux2 ? The second set of continuum flux from
literature (4)
119-122 F4.1 uJy e_lFlux2 ? Error on the second set of continuum
flux from literature
125-127 A3 --- r_lFlux2 Reference for the first set of
continuum flux (4)
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Note (1): For the sources with a detection, we quote their Gaussian fit
(CASA/imfit) results, while for a non detection, the peak emission upper
limit (3-sigma) is shown. The reported flux for REBELS-25 is the integrated
flux, but the peak fluxes for the rest of the sources.
Note (2): The rest-frame 158um continuum flux density is not corrected for the
CMB effect, while the correction has been applied to L_IR.
Note (3): The redshifts are spectroscopic redshifts for the sources with a [CII]
detection, otherwise they are photometric redshifts indicated in the fifth
column.
Note (4): The flux density from literature (uncorrected for the CMB effect) is
taken:
S22 = Schouws et al. (2022ApJ...928...31S 2022ApJ...928...31S)
S21 = Smit et al. (2018Natur.553..178S 2018Natur.553..178S)
B21 = Bowler et al. (2022MNRAS.510.5088B 2022MNRAS.510.5088B)
The two sources from the pilot program, UVISTA-Y-008 and UVISTA-Y-010, are
listed as UVISTA-Y-007 and UVISTA-Y-009, respectively, in Schouws et al.
(2022ApJ...928...31S 2022ApJ...928...31S). The ALMA source names shown in parentheses are the
ones used in the ALMA Science Archive.
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Acknowledgements:
Hanae Inami, hanae hiroshima-u.ac.jp
References:
Bouwens et al., 2022ApJ...931..160B 2022ApJ...931..160B
Reionization Era Bright Emission Line Survey: Selection and characterization
of luminous interstellar medium reservoirs in the z > 6.5 universe
(End) Hanae Inami [Hiroshima University], Patricia Vannier [CDS] 24-Jun-2022