Witnessing the Birth of the Red Sequence: ALMA High-resolution Imaging of [C II] and Dust in Two Interacting Ultra-red Starbursts at z = 4.425
- Autor(en)
- I. Oteo, Rob J. Ivison, L Dunne, Ian R. Smail, A. Mark Swinbank, Helmut Dannerbauer
- Abstrakt
Exploiting the sensitivity and spatial resolution of the Atacama Large Millimeter/submillimeter Array, we have studied the morphology and the physical scale of the interstellar medium—both gas and dust—in SGP 38326, an unlensed pair of interacting starbursts at z = 4.425. SGP 38326 is the most luminous star bursting system known at z > 4, with a total IR luminosity of L IR ~ 2.5 × 1013 L⊙ and a star formation rate of ~ 4500 M⊙ yr-1. SGP 38326 also contains a molecular gas reservoir among the most massive yet found in the early universe, and it is the likely progenitor of a massive, red-and-dead elliptical galaxy at z ~ 3. Probing scales of ~0.″1 or ~800 pc we find that the smooth distribution of the continuum emission from cool dust grains contrasts with the more irregular morphology of the gas, as traced by the [C II] fine structure emission. The gas is also extended over larger physical scales than the dust. The velocity information provided by the resolved [C II] emission reveals that the dynamics of the two interacting components of SGP 38326 are each compatible with disk-like, ordered rotation, but also reveals an ISM which is turbulent and unstable. Our observations support a scenario where at least a subset of the most distant extreme starbursts are highly dissipative mergers of gas-rich galaxies.
- Organisation(en)
- Institut für Astrophysik
- Externe Organisation(en)
- The Royal Observatory, Edinburgh, Durham University
- Journal
- The Astrophysical Journal
- Band
- 827
- Anzahl der Seiten
- 11
- ISSN
- 0004-637X
- DOI
- https://doi.org/10.3847/0004-637X/827/1/34
- Publikationsdatum
- 08-2016
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie, 103004 Astrophysik
- Schlagwörter
- ASJC Scopus Sachgebiete
- Astronomy and Astrophysics, Space and Planetary Science
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/bc4648d3-19f3-4cd7-a45f-4d960b141fa0