Characterization of two 2 mm detected optically obscured dusty star-forming galaxies
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
The 2 mm Mapping Obscuration to Reionization with ALMA (MORA) Survey was designed to detect high-redshift (z ≳ 4), massive, dusty star-forming galaxies (DSFGs). Here we present two likely high-redshift sources, identified in the survey, whose physical characteristics are consistent with a class of optical/near-infrared (OIR)-invisible DSFGs found elsewhere in the literature. We first perform a rigorous analysis of all available photometric data to fit spectral energy distributions and estimate redshifts before deriving physical properties based on our findings. Our results suggest the two galaxies, called MORA-5 and MORA-9, represent two extremes of the “OIR-dark” class of DSFGs. MORA-5 (zphot 4.3 -1.3+1.5) is a significantly more active starburst with a star formation rate (SFR) of 830-190+340M⊙ yr−1 compared to MORA-9 (zphot 4.3 -1.0+1.3), whose SFR is a modest 200-60+250 M⊙ yr−1. Based on the stellar masses (M⋆ ≈ 1010−11 M⊙), space density (n ∼ (5 ± 2) × 10−6 Mpc−3, which incorporates two other spectroscopically confirmed OIR-dark DSFGs in the MORA sample at z = 4.6 and z = 5.9), and gas depletion timescales (<1 Gyr) of these sources, we find evidence supporting the theory that OIR-dark DSFGs are the progenitors of recently discovered 3 < z < 4 massive quiescent galaxies.
Date Issued
2022-01-20
Date Acceptance
2021-11-02
Citation
The Astrophysical Journal (ApJ), 2022, 925 (1)
ISSN
0004-637X
Publisher
IOP Publishing
Journal / Book Title
The Astrophysical Journal (ApJ)
Volume
925
Issue
1
Copyright Statement
© 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
License URL
Identifier
10.3847/1538-4357/ac366a
Subjects
ALMA SURVEY
Astronomy & Astrophysics
COSMOS
FORMATION RATE DENSITY
LEGACY SURVEY
LUMINOSITY FUNCTION
MOLECULAR GAS
MU-M
Physical Sciences
REDSHIFT DISTRIBUTION
Science & Technology
SOURCE CATALOG
SUBMILLIMETER GALAXIES
Publication Status
Published
Article Number
23
Date Publish Online
2022-01-21