A Submillimeter Continuum Survey of Local Dust-Obscured Galaxies

TL;DR

This study surveys dust-obscured galaxies at submillimeter wavelengths, revealing their dust properties and suggesting that dust distribution, not quantity, causes their obscuration.

Contribution

First detailed submillimeter dust analysis of local DOGs, comparing dust properties across different types and with other infrared luminous galaxies.

Findings

Dust temperatures range 22-122 K for warm and cold components.

Total dust mass is 3-34×10^7 M_sun, with small warm dust fractions.

Dust distribution, not total amount, likely causes obscuration in DOGs.

Abstract

We conduct a 350 micron dust continuum emission survey of 17 dust-obscured galaxies (DOGs) at z = 0.05-0.08 with the Caltech Submillimeter Observatory (CSO). We detect 14 DOGs with S_350 = 114-650 mJy and S/N > 3. By including two additional DOGs with submillimeter data in the literature, we are able to study dust contents for a sample of 16 local DOGs that consists of 12 bump and 4 power-law types. We determine their physical parameters with a two-component modified blackbody function model. The derived dust temperatures are in the range 57-122 K and 22-35 K for the warm and cold dust components, respectively. The total dust mass and the mass fraction of warm dust component are 3-34$\times10^{7} M_\odot$ and 0.03-2.52%, respectively. We compare these results with those of other submillimeter-detected infrared luminous galaxies. The bump DOGs, the majority of the DOG sample, show similar distributions of dust temperatures and total dust mass to the comparison sample. The power-law DOGs show a hint of smaller dust masses than other samples, but need to be tested with a larger sample. These findings support that the reason why DOGs show heavy dust obscuration is not an overall amount of dust content, but probably the spatial distribution of dust therein.