J/ApJ/923/215 MORA: ALMA 2mm survey (Casey+, 2021)
Mapping Obscuration to Reionization with ALMA (MORA): 2mm efficiently selects
the highest-redshift obscured galaxies.
Casey C.M., Zavala J.A., Manning S.M., Aravena M., Bethermin M.,
Caputi K.I., Champagne J.B., Clements D.L., Drew P., Finkelstein S.L.,
Fujimoto S., Hayward C.C., Dekel A.M., Kokorev V., del Lagos C. P,
Long A.S., Magdis G.E., Man A.W.S., Mitsuhashi I., Popping G., Spilker J.,
Staguhn J., Talia M., Toft S., Treister E., Weaver J.R., Yun M.
<Astrophys. J., 923, 215 (2021)>
=2021ApJ...923..215C 2021ApJ...923..215C
ADC_Keywords: Photometry, millimetric/submm; Surveys; Galaxies; Redshifts;
Active gal. nuclei; Photometry, infrared; Radio sources
Keywords: Millimeter astronomy ; Submillimeter astronomy ;
Dust continuum emission ; High-redshift galaxies ; Active galaxies ;
Infrared galaxies ; Starburst galaxies
Abstract:
We present the characteristics of 2mm selected sources from the
largest Atacama Large Millimeter/submillimeter Array (ALMA)
blank-field contiguous survey conducted to date, the Mapping
Obscuration to Reionization with ALMA (MORA) survey covering
184arcmin2 at 2mm. Twelve of 13 detections above 5σ are
attributed to emission from galaxies, 11 of which are dominated by
cold dust emission. These sources have a median redshift of
<z2mm≥3.6-0.3+0.4 primarily based on optical/near-infrared
photometric redshifts with some spectroscopic redshifts, with
77%±11% of sources at z>3 and 38%±12% of sources at z>4. This
implies that 2mm selection is an efficient method for identifying the
highest-redshift dusty star-forming galaxies (DSFGs). Lower-redshift
DSFGs (z<3) are far more numerous than those at z>3 yet are likely to
drop out at 2mm. MORA shows that DSFGs with star formation rates in
excess of 300M☉/yr and a relative rarity of ∼10-5Mpc-3
contribute ∼30% to the integrated star formation rate density at
3<z<6. The volume density of 2mm selected DSFGs is consistent with
predictions from some cosmological simulations and is similar to the
volume density of their hypothesized descendants: massive, quiescent
galaxies at z>2. Analysis of MORA sources' spectral energy
distributions hint at steeper empirically measured dust emissivity
indices than reported in typical literature studies, with
<β≥2.2-0.4+0.5. The MORA survey represents an important step
in taking census of obscured star formation in the universe's first
few billion years, but larger area 2mm surveys are needed to more
fully characterize this rare population and push to the detection of
the universe's first dusty galaxies.
Description:
Observations with the Atacama Large Millimeter and submillimeter Array
(ALMA) were carried out under program 2018.1.00231.S from 2019-March-27
through 2019-April-3 in the C43-3 configuration for a total of 14.6hr
including overheads and calibrations.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 147 12 *Measured physical characteristics of the 2mm
detected sample
table3.dat 182 13 Photometry of the >5σ 2mm sample
table4.dat 84 98 Positions and multiwavelength counterparts for the
marginal 4<σ<5 2mm sample
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Note on table2.dat: Estimates for ISM masses (not given in this table) can be
obtained by multiplying the dust masses in this table by a factor of
125 (Remy-Ruyer+ 2014A&A...563A..31R 2014A&A...563A..31R).
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See also:
II/284 : COSMOS Multi-Wavelength Photometry Catalog (Capak+, 2007)
VIII/103 : Herschel Multi-tiered Extragalactic Survey (Oliver+, 2012)
VIII/95 : Herschel Multi-tiered Extragalactic Survey (Oliver+, 2012)
J/ApJ/554/803 : New VLA Sky Survey (NVSS) of IRAS 2 Jy Galaxies (Yun+ 2001)
J/ApJ/622/772 : Redshift survey of submillimeter galaxies (Chapman+, 2005)
J/ApJS/172/46 : VLA-COSMOS survey. II. (Schinnerer+, 2007)
J/MNRAS/385/2225 : AzTEC millimetre survey of COSMOS field (Scott+, 2008)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/MNRAS/415/3831 : AzTEC/ASTE source catalogue (Aretxaga+, 2011)
J/A+A/532/A90 : PACS Evolutionary Probe (PEP-DR1) catalogs (Lutz+, 2011)
J/ApJ/735/86 : NEWFIRM MBS: photometric catalogs (Whitaker+, 2011)
J/ApJS/201/30 : The Chandra COSMOS survey. III. (Civano+, 2012)
J/MNRAS/436/1919 : SCUBA observations of COSMOS galaxies (Casey+, 2013)
J/ApJ/768/91 : ALMA observations of LESS submm galaxies (Hodge+, 2013)
J/A+A/556/A55 : Multi-color phot. of star-forming galaxies (Ilbert+, 2013)
J/ApJ/777/18 : Stellar mass functions of galaxies to z=4 (Muzzin+, 2013)
J/MNRAS/436/430 : SCUBA-2 cosmology legacy survey (Roseboom+, 2013)
J/ApJS/218/33 : Spitzer-CANDELS catalog within 5 deep fields (Ashby+, 2015)
J/ApJ/806/110 : ALESS survey: SMGs in the ECDF-S data (da Cunha+, 2015)
J/ApJ/810/71 : UV mag of cand. galaxies at 3~<z~<8.5 (Finkelstein+, 2015)
J/ApJ/819/62 : The COSMOS-Legacy Survey (CLS) catalog (Civano+, 2016)
J/ApJ/832/78 : SCUBA2 & LABOCA obs. of HATLAS ultrared gal. (Ivison+, 2016)
J/ApJS/224/24 : The COSMOS2015 catalog (Laigle+, 2016)
J/ApJ/820/83 : ALMA galaxies in the COSMOS survey field (Scoville+, 2016)
J/A+A/608/A15 : ALMA survey of submm gal. in COSMOS field (Brisbin+, 2017)
J/ApJ/850/83 : DANCING-ALMA. I. submm/mm cont. sources (Fujimoto+, 2017)
J/MNRAS/465/1789 : SCUBA-2 Cosmology Legacy Survey (Geach+, 2017)
J/MNRAS/469/492 : JCMT/SCUBA2 objects in COSMOS & UDS (Michalowski+ 2017)
J/A+A/602/A1 : VLA-COSMOS 3 GHz Large Project (Smolcic+, 2017)
J/MNRAS/473/1751 : Herschel Bright Sources (HerBS) (Bakx+, 2018)
J/A+A/614/A33 : 500µm-risers sources (Donevski+, 2018)
J/MNRAS/477/1099 : SCUBA-2 850um obs. of Herschel gal. (Duivenvoorden+, 2018)
J/ApJ/853/172 : "Super-deblended" dust emission in galaxies. I. (Liu+, 2018)
J/A+A/618/A85 : Spectroscopy of 3<z<4 quiescent galaxies (Schreiber+ 2018)
J/A+A/611/A22 : Jekyll & Hyde galaxies ALMA cube & sp. (Schreiber+, 2018)
J/MNRAS/490/3309 : Massive passive galaxies at the Cosmic Dawn (Merlin+, 2019)
J/ApJ/880/43 : S2COSMOS: SCUBA-2 submm sources in COSMOS (Simpson+, 2019)
J/ApJ/903/139 : COSMOS-XS. II. Ultra-faint radio population (Algera+, 2020)
J/ApJS/249/1 : 500um risers with HerMES (Yan+, 2020)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- MORA MORA designation (MORA-NN, from 1 to 11)
9- 13 F5.3 --- z [2.29/5.85] Redshift
15- 18 F4.2 --- e_z [0.05/1.3]? Lower uncertainty on z (1)
20- 23 F4.2 --- E_z [0.05/1.5]? Upper uncertainty on z (1)
25- 30 A6 --- zType Type of z (OIR=optical/near-infrared)
32- 38 E7.3 Lsun LIR [1.2e+12/2e+13] IR luminosity
40- 46 E7.3 Lsun e_LIR [4e+11/3e+12] Lower uncertainty on LIR (1)
48- 54 E7.3 Lsun E_LIR [5e+11/4.7e+12] Upper uncertainty on LIR (1)
56- 59 I4 Msun/yr SFR [180/3000] Star formation rate
61- 63 I3 Msun/yr e_SFR [60/400] Lower uncertainty on SFR (1)
65- 67 I3 Msun/yr E_SFR [70/700] Upper uncertainty on SFR (1)
69- 71 I3 um lamPk [68/133] SED peak wavelength, λpeak
73- 74 I2 um e_lamPk [4/23] Lower uncertainty on lamPk (1)
76- 77 I2 um E_lamPk [4/26] Upper uncertainty on lamPk (1)
79 A1 --- f_beta [e] e=Variables that have been fixed
80- 83 F4.2 --- beta [0/3.11] Dust emissivity index, β
85- 88 F4.2 --- e_beta [0.1/0.5]? Lower uncertainty on beta (1)
90- 93 F4.2 --- E_beta [0.1/0.4]? Upper uncertainty on beta (1)
95 A1 --- f_alpha [e] e=Variables that have been fixed
96- 98 F3.1 --- alpha [0/7] Mid-IR power-law slope, αMIR
100- 103 F4.2 --- e_alpha [0.14/2.9]? Lower uncertainty on alpha (1)
105- 108 F4.2 --- E_alpha [0.15/3]? Upper uncertainty on alpha (1)
110- 114 E5.2 Msun Mdust [2.1e+08/1.4e+09] Dust mass
116- 120 E5.2 Msun e_Mdust [6e+07/4e+08] Lower uncertainty on Mdust (1)
122- 126 E5.2 Msun E_Mdust [5e+07/5.1e+08] Upper uncertainty on Mdust (1)
128- 133 E6.2 Msun Mstar [3.2e+09/2.5e+11]? Stellar mass (2)
135- 140 E6.2 Msun e_Mstar [1.5e+09/7e+10]? Lower uncertainty on Mstar (1)
142- 147 E6.2 Msun E_Mstar [1e+09/1e+11]? Upper uncertainty on Mstar (1)
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Note (1): All uncertainties in this table indicate the inner 68% minimum
credible interval of posterior distributions.
Note (2): A stellar mass estimate is not available for MORA-3 (AzTEC-2) due to
blending of near-infrared imaging with foreground galaxies.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- MORA MORA designation (MORA-NN, from 1 to 12)
9 A1 --- n_MORA [n] Note on MORA-12 (3)
11- 12 I2 h RAh [10] Hour of right ascension (J2000)
14- 15 I2 min RAm [0] Minute of right ascension (J2000)
17- 22 F6.3 s RAs Second of right ascension (J2000)
24 A1 --- DE- [+] Sign of declination (J2000)
25- 26 I2 deg DEd [2] Degree of declination (J2000)
28- 29 I2 arcmin DEm Arcminute of declination (J2000)
31- 35 F5.2 arcsec DEs Arcsecond of declination (J2000)
37- 40 F4.2 --- S/N [5/8] Signal-to-noise ratio at 2mm
42- 45 I4 uJy S2mm [356/1220] ALMA 2mm flux density
47- 49 I3 uJy e_S2mm [60/190] S2mm uncertainty
51- 55 F5.2 mag Hmag [22.6/26.8]? H-band AB magnitude
57- 60 F4.2 mag e_Hmag [0.01/0.3]? Uncertainty on the Hmag
61 A1 --- f_Hmag [n] n: nondetection in the COSMOS2020 catalog
63 A1 --- l_S3.6 [l] Limit flag on S3.6; <3σ detections
64- 68 I5 nJy S3.6 [1/13322]? Spitzer/IRAC 3.6um flux density
70- 72 I3 nJy e_S3.6 [24/199]? S3.6 uncertainty
74 A1 --- l_S24 [l] Limit flag on S24; <3σ detections
75- 77 I3 uJy S24 [-8/890]? Spitzer/MIPS 24um flux density
79- 80 I2 uJy e_S24 [12/44]? S24 uncertainty
82 A1 --- l_S100 [l] Limit flag on S100; <3σ detections
83- 86 F4.1 mJy S100 [-1.7/6] Herschel/PACS 100um flux density
88- 90 F3.1 mJy e_S100 [1.5/2] S100 uncertainty
92 A1 --- l_S160 [l] Limit flag on S160; <3σ detections
93- 96 F4.1 mJy S160 [-0.6/31.4] Herschel/PACS 160um flux density
98-100 F3.1 mJy e_S160 [2.8/4] S160 uncertainty
102 A1 --- l_S250 [l] Limit flag on S250; <3σ detections
103-106 F4.1 mJy S250 [0/38] Herschel/SPIRE 250um flux density
108-111 F4.1 mJy e_S250 [5.8/16] S250 uncertainty
113 A1 --- l_S350 [l] Limit flag on S350; <3σ detections
114-117 F4.1 mJy S350 [0/48.4] Herschel/SPIRE 350um flux density
119-122 F4.1 mJy e_S350 [6.3/20.3] S350 uncertainty
124 A1 --- l_S450 [l] Limit flag on S450; <3σ detections
125-128 F4.1 mJy S450 [1/40.6] SCUBA-2 450um flux density
130-133 F4.1 mJy e_S450 [4/14.4] S450 uncertainty
135 A1 --- l_S500 [l] Limit flag on S500; <3σ detections
136-139 F4.1 mJy S500 [0/42] Herschel/SPIRE 500um flux density
141-144 F4.1 mJy e_S500 [6.8/26] S500 uncertainty
146 A1 --- l_S850 [l] Limit flag on S850; <3σ detections
147-152 F6.3 mJy S850 [0.2/16.8] SCUBA-2 850um flux density
154-158 F5.3 mJy e_S850 [0.05/0.8] S850 uncertainty
159 A1 --- f_S850 [d] d: the flux density in the S850 column has
been replaced by improved 870um photometry
from ALMA rather than SCUBA-2
161-164 F4.2 mJy S1.2mm [1.49/4.7]? 1.2mm flux density
166-169 F4.2 mJy e_S1.2mm [0.05/0.2]? S1.2mm uncertainty
171 A1 --- l_S3GHz [l] Limit flag on S3GHz; <3σ detections
172-177 F6.1 uJy S3GHz [1/3212] VLA 3GHz flux density from
Smolcic+ 2017, J/A+A/602/A1
179-181 F3.1 uJy e_S3GHz [0.8/4.1] S3GHz uncertainty
182 A1 --- f_S3GHz [*] *: S3GHz from COSMOS-XS maps (G1)
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Note (3): Note as follows:
n = MORA-12, is detected at 5.02σ significance; unlike the rest of
the >5σ sample, it has no corresponding detection at 850um. This
source is the only source in the >5σ sample to lack detection in
Spitzer IRAC at 3.6um or 4.5um. There is no additional ALMA data
at any other wavelength at the position of MORA-12. With only one
detection at one wavelength, we are unable to derive a millimeter
photometric redshift for this source. We conclude it is most likely
that MORA-12 is not real and that it is a positive noise peak.
See Section 3.3.13.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Name Main name of the source
13- 14 I2 h RAh [10] Hour of right ascension (J2000)
16- 17 I2 min RAm [0] Minute of right ascension (J2000)
19- 24 F6.3 s RAs Second of right ascension (J2000)
26 A1 --- DE- [+] Sign of declination (J2000)
27- 28 I2 deg DEd [2] Degree of declination (J2000)
30- 31 I2 arcmin DEm Arcminute of declination (J2000)
33- 37 F5.2 arcsec DEs Arcsecond of declination (J2000)
39- 42 F4.2 --- S/N [4/4.8] Signal-to-noise ratio at 2mm
44- 47 I4 --- S2mm [256/1140] ALMA 2mm flux density
49- 51 I3 --- e_S2mm [62/268] S2mm uncertainty
53- 57 F5.2 mag Hmag [18.94/26.81]? H-band AB magnitude
59- 62 F4.2 mag e_Hmag [0.01/0.5]? Uncertainty on the Hmag
64- 68 F5.2 --- S850 [2.5/10.5]? SCUBA-2 850um flux density
70- 73 F4.2 --- e_S850 [0.5/0.7]? S850 uncertainty
75- 79 F5.1 --- S3GHz [6.4/259]? VLA 3GHz flux density
81- 83 F3.1 --- e_S3GHz [0.9/4]? S3GHz uncertainty
84 A1 --- f_S3GHz Flag on S3GHz (G1)
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Global notes:
Note (G1): Flag as follows:
* = the 3GHz flux density comes from the deeper COSMOS-XS maps of
van der Vlugt+ (2021ApJ...907....5V 2021ApJ...907....5V) and Algera+ (2020, J/ApJ/903/139)
rather than the shallower/wider coverage of Smolcic+ 2017, J/A+A/602/A1
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 26-May-2023