{
  "id": "1705.09826",
  "version": "v1",
  "published": "2017-05-27T14:55:06.000Z",
  "updated": "2017-05-27T14:55:06.000Z",
  "title": "VALES: I. The molecular gas content in star-forming dusty H-ATLAS galaxies up to z=0.35",
  "authors": [
    "V. Villanueva",
    "E. Ibar",
    "T. M. Hughes",
    "M. A. Lara-López",
    "L. Dunne",
    "S. Eales",
    "R. J. Ivison",
    "M. Aravena",
    "M. Baes",
    "N. Bourne",
    "P. Cassata",
    "A. Cooray",
    "H. Dannerbauer",
    "L. J. M. Davies",
    "S. P. Driver",
    "S. Dye",
    "C. Furlanetto",
    "R. Herrera-Camus",
    "S. J. Maddox",
    "M. J. Michalowski",
    "J. Molina",
    "D. Riechers",
    "A. E. Sansom",
    "M. W. L. Smith",
    "G. Rodighiero",
    "E. Valiante",
    "P. van der Werf"
  ],
  "comment": "Accepted for publication in MNRAS. 31 pages, including 9 figures and 2 tables",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We present an extragalactic survey using observations from the Atacama Large Millimeter/submillimeter Array (ALMA) to characterise galaxy populations up to $z=0.35$: the Valpara\\'iso ALMA Line Emission Survey (VALES). We use ALMA Band-3 CO(1--0) observations to study the molecular gas content in a sample of 67 dusty normal star-forming galaxies selected from the $Herschel$ Astrophysical Terahertz Large Area Survey ($H$-ATLAS). We have spectrally detected 49 galaxies at $>5\\sigma$ significance and 12 others are seen at low significance in stacked spectra. CO luminosities are in the range of $(0.03-1.31)\\times10^{10}$ K km s$^{-1}$ pc$^2$, equivalent to $\\log({\\rm M_{gas}/M_{\\odot}}) =8.9-10.9$ assuming an $\\alpha_{\\rm CO}$=4.6(K km s$^{-1}$ pc$^{2}$)$^{-1}$, which perfectly complements the parameter space previously explored with local and high-z normal galaxies. We compute the optical to CO size ratio for 21 galaxies resolved by ALMA at $\\sim 3$.''$5$ resolution (6.5 kpc), finding that the molecular gas is on average $\\sim$ 0.6 times more compact than the stellar component. We obtain a global Schmidt-Kennicutt relation, given by $\\log [\\Sigma_{\\rm SFR}/({\\rm M_{\\odot} yr^{-1}kpc^{-2}})]=(1.26 \\pm 0.02) \\times \\log [\\Sigma_{\\rm M_{H2}}/({\\rm M_{\\odot}\\,pc^{-2}})]-(3.6 \\pm 0.2)$. We find a significant fraction of galaxies lying at `intermediate efficiencies' between a long-standing mode of star-formation activity and a starburst, specially at $\\rm L_{IR}=10^{11-12} L_{\\odot}$. Combining our observations with data taken from the literature, we propose that star formation efficiencies can be parameterised by $\\log [{\\rm SFR/M_{H2}}]=0.19 \\times {\\rm (\\log {L_{IR}}-11.45)}-8.26-0.41 \\times \\arctan[-4.84 (\\log {\\rm L_{IR}}-11.45) ]$. Within the redshift range we explore ($z<0.35$), we identify a rapid increase of the gas content as a function of redshift.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-05-27T14:55:06.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "molecular gas content",
      "star-forming dusty h-atlas galaxies",
      "terahertz large area survey",
      "normal star-forming galaxies",
      "valparaiso alma line emission survey"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 31,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}