New hot DOG in the sky: Astronomers discover a hot-dust-obscured galaxy

A global workforce of astronomers experiences the detection of a brand new, hot-dust-obscured galaxy (DOG). The galaxy, which obtained designation WISE J190445.04+485308.9, was discovered at a comparatively low redshift of 0.415, which makes it the primary confirmed low-redshift sizzling DOG. The invention was introduced in a paper revealed Could 23 on the arXiv preprint server.

Quasars are galaxies with extraordinarily energetic lively galactic nuclei (AGNs). Scorching DOGs are a uncommon kind of hyper-luminous obscured quasars recognized with Broad-field Infrared Survey Explorer (WISE), particularly labeled for being detected by way of their dust emission. In comparison with typical dust-obscured galaxies, sizzling DOGs are considerably redder in WISE passbands attributable to their hotter dust emission heated by the AGN and have a lot greater bolometric luminosities.

Not too long ago, a bunch of astronomers led by Guodong Li of College of Chinese language Academy of Sciences in Beijing, China, has detected one other quasar of this uncommon kind. By analyzing the info from WISE and varied ground-based telescopes, they discovered a brand new hyper-luminous, highly-obscured AGN and designated it WISE J190445.04+485308.9 (or W1904+4853 for brief).

“Its well-sampled spectral power distribution (SED) is dominated by infrared dust emission, although broad emission traces are detected within the optical spectra. These options recommend that W1904+4853 accommodates an actively accreting supermassive black hole hidden in its dusty cocoon, resembling the noticed properties of sizzling Mud-Obscured Galaxies (sizzling DOGs), a inhabitants beforehand solely recognized at z > 1.0,” the researchers defined.

Based on the research, W1904+4853 has a stellar mass of about 30 billion solar plenty and its bolometric luminosity is 11 trillion solar luminosities. The supermassive black hole (SMBH) of W1904+4853 is assumed to be accreting at near the Eddington restrict.

The astronomers discovered that the Infrared dust emission contributes to roughly 99% of the bolometric luminosity of W1904+4853, dominating the total power output of this galaxy. The total dust mass was calculated to be some 50 million solar plenty, whereas the dust temperature was estimated to achieve 539 Ok. The researchers assume that within the case of W1904+4853, the dust near the AGN is heated by the accreting SMBH to greater temperatures than of different infrared-luminous galaxies.

By analyzing the spectral power distribution (SED) of W1904+4853, the authors of the research discovered that the galaxy is surprisingly dominated by the younger stellar inhabitants, with a star formation charge at a stage of 45 solar masses per 12 months. This star formation seems to contribute to solely 8percentt of the far-infrared luminosity, additional supporting the state of affairs wherein the infrared dust emission is powered by the AGN.

The analysis additionally discovered ionized gasoline outflows from the central obscured AGN of W1904+4853. It turned out that the outflow mass is an order of magnitude lower than the continuing star formation charge of the host galaxy, which, in line with the researchers, means that the outflow energy has not been totally launched but to drive the star-forming materials out of the system.

“Though blueshifted and uneven [O III] emission gives proof of an outflow, we estimate it to be an order of magnitude smaller than the star formation rate, indicating that the present obscured AGN exercise on the heart has not but produced important suggestions on the host galaxy star formation exercise,” the astronomers concluded.

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