Abstract
Submillimeter/millimeter observations of dusty star-forming galaxies
with the Atacama Large Millimeter/submillimeter Array (ALMA) have shown
that dust continuum emission generally occurs in compact regions smaller
than the stellar distribution. However, it remains to be understood how
systematic these findings are. Studies often lack homogeneity in the
sample selection, target discontinuous areas with inhomogeneous
sensitivities, and suffer from modest uv coverage coming from single array configurations. GOODS-ALMA is a 1.1 mm galaxy survey over a continuous area of 72.42 arcmin2
at a homogeneous sensitivity. In this version 2.0, we present a new low
resolution dataset and its combination with the previous high
resolution dataset from the survey, improving the uv coverage and sensitivity reaching an average of σ = 68.4 μJy beam−1. A total of 88 galaxies are detected in a blind search (compared to 35 in the high resolution dataset alone), 50% at S/Npeak ≥ 5 and 50% at 3.5 ≤ S/Npeak ≤ 5 aided by priors. Among them, 13 out of the 88 are optically dark or faint sources (H- or K-band dropouts). The sample dust continuum sizes at 1.1 mm are generally compact, with a median effective radius of Re = 0.″10 ± 0.″05 (a physical size of Re = 0.73 ± 0.29
kpc at the redshift of each source). Dust continuum sizes evolve with
redshift and stellar mass resembling the trends of the stellar sizes
measured at optical wavelengths, albeit a lower normalization compared
to those of late-type galaxies. We conclude that for sources with flux
densities S1.1 mm > 1 mJy, compact dust continuum
emission at 1.1 mm prevails, and sizes as extended as typical
star-forming stellar disks are rare. The S1.1 mm <
1 mJy sources appear slightly more extended at 1.1 mm, although they
are still generally compact below the sizes of typical star-forming
stellar disks.
Original language | English |
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Article number | A43 |
Journal | Astronomy and Astrophysics |
Volume | 658 |
Number of pages | 29 |
ISSN | 0004-6361 |
DOIs | |
Publication status | Published - 2022 |
Keywords
- Galaxies: evolution
- Galaxies: high-redshift
- Galaxies: photometry
- Galaxies: star formation
- Galaxies: structure
- Submillimeter: galaxies