2026-06-27T23:05:35Zhttps://docta.ucm.es/rest/oai/request

oai:docta.ucm.es:20.500.14352/139002023-08-27T02:33:16Zcom_20.500.14352_14col_20.500.14352_15

Pérez González, Pablo Guillermo 2023-06-17T13:38:23Z 2023-06-17T13:38:23Z 2019-09-09 0004-637X 10.3847/1538-4357/ab3791 https://hdl.handle.net/20.500.14352/13900 http://dx.doi.org/10.3847/1538-4357/ab3791 https://iopscience.iop.org We present high-fidelity, 30 mas (200 pc) resolution ALMA rest-frame 240 μm observations of cold dust emission in three typical main-sequence star-forming galaxies (SFGs) at z ∼ 3 in the Hubble Ultra-Deep Field (HUDF). The cold dust is distributed within the smooth disklike central regions of star formation 1–3 kpc in diameter, despite their complex and disturbed rest-frame UV and optical morphologies. No dust substructures or clumps are seen down to ∼1–3 Mꙩ yr−1 (1σ) per 200 pc beam. No dust emission is observed at the locations of UV-emitting clumps, which lie ∼2–10 kpc from the bulk of star formation. Clumpy substructures can contribute no more than 1%–7% of the total star formation in these galaxies (3σ upper limits). The lack of star-forming substructures in our HUDF galaxies is to be contrasted with the multiple substructures characteristic of submillimeter-selected galaxies (SMGs) at the same cosmic epoch, particularly the far-IR-bright SMGs with similarly high-fidelity ALMA observations of Hodge et al. Individual star-forming substructures in these SMGs contain ∼10%–30% of their total star formation. A substructure in these SMGs is often comparably bright in the far-infrared to (or in some cases brighter than) our typical SFGs, suggesting that these SMGs originate from a class of disruptive events involving multiple objects at the scale of our HUDF galaxies. The scale of the disruptive event found in our main-sequence SFGs, characterized by the lack of star-forming substructures at our resolution and sensitivity, could be less violent, e.g., gas-rich disk instability or minor mergers. eng open access ALMA 200 pc resolution imaging of smooth cold dusty disks in typical z ∼ 3 star-forming galaxies journal article