Three-dimensional Distribution of the Interstellar Dust in the Milky Way
Abstract
We present a three-dimensional (3D) extinction map of the southern sky. The map covers the SkyMapper Southern Survey (SMSS) area of ∼14,000 deg2 and has spatial resolutions between 6'9 and 27'. Based on the multi-band photometry of SMSS, the Two Micron All Sky Survey, the Wide-Field Infrared Survey Explorer Survey, and the Gaia mission, we have estimated values of the r-band extinction for ∼19 million stars with the spectral energy distribution analysis. Together with the distances calculated from the Gaia data release 2 (DR2) parallaxes, we have constructed a 3D extinction map of the southern sky. By combining our 3D extinction map with those from the literature, we present an all-sky 3D extinction map, and use it to explore the 3D distribution of the Galactic dust grains. We use two different models, one consisting of a single disk and another of two disks, to fit the 3D distribution of the Galactic dust grains. The data is better fitted by a two-disk model, yielding smaller values of the Bayesian Information Criterion. The best-fit model has scale heights of 73 and 225 pc for the "thin" and "thick" dust disks, respectively.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 2021
- DOI:
- 10.3847/1538-4357/abc68a
- arXiv:
- arXiv:2010.14092
- Bibcode:
- 2021ApJ...906...47G
- Keywords:
-
- Interstellar dust;
- Interstellar dust extinction;
- Galaxy structure;
- the Milky Way;
- 836;
- 837;
- 622;
- 1054;
- Astrophysics - Astrophysics of Galaxies;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- 18 pages, 14 figures, accepted for publication in ApJ, data avaiable via https://nadc.china-vo.org/article/20200722160959?id=101032