{
  "id": "1511.07145",
  "version": "v1",
  "published": "2015-11-23T09:27:45.000Z",
  "updated": "2015-11-23T09:27:45.000Z",
  "title": "The ATLASGAL survey: distribution of cold dust in the Galactic plane. Combination with Planck data",
  "authors": [
    "T. Csengeri",
    "A. Weiss",
    "F. Wyrowski",
    "K. M. Menten",
    "J. S. Urquhart",
    "S. Leurini",
    "F. Schuller",
    "H. Beuther",
    "S. Bontemps",
    "L. Bronfman",
    "Th. Henning",
    "N. Schneider"
  ],
  "comment": "Accepted for publication in A&A. 10 pages, 10 figures, abstract is shortened",
  "categories": [
    "astro-ph.SR",
    "astro-ph.GA"
  ],
  "abstract": "Sensitive ground-based submillimeter surveys, such as ATLASGAL, provide a global view on the distribution of cold dense gas in the Galactic plane. Here we use the 353 GHz maps from the Planck/HFI instrument to complement the ground-based APEX/LABOCA observations with information on larger angular scales. The resulting maps reveal the distribution of cold dust in the inner Galaxy with a larger spatial dynamic range. We find examples of elongated structures extending over angular scales of 0.5 degree. Corresponding to >30 pc structures in projection at a distance of 3 kpc, these dust lanes are very extended and show large aspect ratios. Furthermore, we assess the fraction of dense gas ($f_{\\rm DG}$), and estimate 2-5% (above A$_{\\rm{v}}>$7 mag) on average in the Galactic plane. PDFs of the column density reveal the typically observed log-normal distribution for low- and exhibit an excess at high column densities. As a reference for extragalactic studies, we show the line-of-sight integrated N-PDF of the inner Galaxy, and derive a contribution of this excess to the total column density of $\\sim2.2$%, above $N_{\\rm H_2} = 2.92\\times10^{22}$ cm$^{-2}$. Taking the total flux density, we provide an independent estimate of the mass of molecular gas in the inner Galaxy of $\\sim1\\times10^9\\,M_{\\odot}$, which is consistent with previous estimates using CO emission. From the mass and $f_{\\rm DG}$ we estimate a Galactic SFR of $\\dot M = 1.3\\,M_{\\odot}$ yr$^{-1}$. While the distribution of diffuse gas is homogenous in the inner Galaxy, the CMZ stands out with a higher dense gas fraction. The low star formation efficiency of the Milky Way is well explained by the low $f_{\\rm DG}$ in the Galactic ISM, while the high $f_{\\rm DG}$ towards the CMZ, despite its low star formation activity, suggests that, in that particular region of our Galaxy, high-density gas is not the bottleneck for star formation.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-11-23T09:27:45.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "galactic plane",
      "cold dust",
      "atlasgal survey",
      "planck data",
      "distribution"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}