National Astronomical Observatory of Japan | ALMA | 2018 Feb 20
The co-evolution mystery deepened by a new ALMA observation
Using the Atacama Large Millimeter/submillimeter Array (ALMA) to observe an active galaxy with a strong ionized gas outflow from the galactic center, a team led by Dr. Yoshiki Toba has obtained a result making astronomers even more puzzled -- the team clearly detected carbon monoxide (CO) gas that is associated with the galactic disk, yet they have also found that the CO gas which settles in the galaxy is not affected by the strong ionized gas outflow launched from the galactic center.
According to a popular scenario explaining the formation and evolution of galaxies and supermassive black holes, radiation from galactic centers -- where supermassive black holes locate -- can significantly influence the molecular gas (such as CO) and the star formation activities of the galaxies. With an ALMA result showing that the ionized gas outflow driven by the supermassive black hole does not necessarily affect its host galaxy ...
The gas outflow driven by a supermassive black hole at the galactic center recently has become the focus of attention as it possibly is playing a key role in the co-evolution of galaxies and black holes. A widely accepted idea has described this phenomenon as: the strong radiation from the galactic center in which the supermassive black hole locates ionizes [1] the surrounding gas and affects even molecular gas that is the ingredient of star formation; the strong radiation activates [2] or suppresses [3] the star formation of galaxies. ...
The team has focused on a particular type of objects called Dust-Obscured Galaxy (DOG) that has a prominent feature: despite being very faint in the visible light, it is very bright in the infrared. (Figure 1).
Astronomers are believing that DOGs harbor actively growing supermassive black holes in their nuclei [4]. In particular, one DOG (WISE 1029+0501, hereafter WISE 1029) is outflowing gas ionized by the strong radiation from its supermassive black hole. WISE 1029 is known as an extreme case in terms of ionized gas outflow, and this particular factor has motivated the researchers to see what happens to its molecular gas. ...
No Sign of Strong Molecular Gas Outflow in an Infrared-Bright
Dust-Obscured Galaxy with Strong Ionized-Gas Outflow - Yoshiki Toba et al
- Astrophysical Journal 851(2):98 (2017 Dec 20) DOI: 10.3847/1538-4357/aa9d17
arXiv.org > astro-ph > arXiv:1711.10091 > 28 Nov 2017