{
  "id": "1511.07432",
  "version": "v1",
  "published": "2015-11-23T21:00:01.000Z",
  "updated": "2015-11-23T21:00:01.000Z",
  "title": "Bright [CII] and dust emission in three z>6.6 quasar host galaxies observed by ALMA",
  "authors": [
    "B. P. Venemans",
    "F. Walter",
    "L. Zschaechner",
    "R. Decarli",
    "G. De Rosa",
    "J. R. Findlay",
    "R. G. McMahon",
    "W. J. Sutherland"
  ],
  "comment": "16 pages, 12 figures. Accepted for publication in ApJ",
  "categories": [
    "astro-ph.GA",
    "astro-ph.CO"
  ],
  "abstract": "We present ALMA detections of the [CII] 158 micron emission line and the underlying far-infrared continuum of three quasars at 6.6<z<6.9 selected from the VIKING survey. The [CII] line fluxes range between 1.6-3.4 Jy km/s ([CII] luminosities ~(1.9-3.9)x10^9 L_sun). We measure continuum flux densities of 0.56-3.29 mJy around 158 micron (rest-frame), with implied far-infrared luminosities between (0.6-7.5)x10^12 L_sun and dust masses M_d=(0.7-24)x10^8 M_sun. In one quasar we derive a dust temperature of 30^+12_-9 K from the continuum slope, below the canonical value of 47 K. Assuming that the [CII] and continuum emission are powered by star formation, we find star-formation rates from 100-1600 M_sun/yr based on local scaling relations. The L_[CII]/L_FIR ratios in the quasar hosts span a wide range from (0.3-4.6)x10^-3, including one quasar with a ratio that is consistent with local star-forming galaxies. We find that the strength of the L_[CII] and 158 micron continuum emission in z>~6 quasar hosts correlate with the quasar's bolometric luminosity. In one quasar, the [CII] line is significantly redshifted by ~1700 km/s with respect to the MgII broad emission line. Comparing to values in the literature, we find that, on average, the MgII is blueshifted by 480 km/s (with a standard deviation of 630 km/s) with respect to the host galaxy redshift, i.e. one of our quasars is an extreme outlier. Through modeling we can rule out a flat rotation curve for our brightest [CII] emitter. Finally, we find that the ratio of black hole mass to host galaxy (dynamical) mass is higher by a factor 3-4 (with significant scatter) than local relations.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-11-23T21:00:01.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "quasar host galaxies",
      "dust emission",
      "mgii broad emission line",
      "black hole mass",
      "quasar hosts correlate"
    ],
    "publication": {
      "doi": "10.3847/0004-637X/816/1/37"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 16,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1406084
    }
  }
}