{
  "id": "2004.13125",
  "version": "v1",
  "published": "2020-04-27T19:49:09.000Z",
  "updated": "2020-04-27T19:49:09.000Z",
  "title": "The GLEAM 4-Jy (G4Jy) Sample: I. Definition and the catalogue",
  "authors": [
    "Sarah V. White",
    "Thomas M. O. Franzen",
    "Chris J. Riseley",
    "O. Ivy Wong",
    "Anna D. Kapińska",
    "Natasha Hurley-Walker",
    "Joseph R. Callingham",
    "Kshitij Thorat",
    "Chen Wu",
    "Paul Hancock",
    "Richard W. Hunstead",
    "Nick Seymour",
    "Jesse Swan",
    "Randall Wayth",
    "John Morgan",
    "Rajan Chhetri",
    "Carole Jackson",
    "Stuart Weston",
    "Martin Bell",
    "Bi-Qing For",
    "B. M. Gaensler",
    "Melanie Johnston-Hollitt",
    "André Offringa",
    "Lister Staveley-Smith"
  ],
  "comment": "57 pages (30 MB in size), 23 figures, 16 tables, accepted for publication in PASA. Full-resolution images will be used for the published version, available through the journal. To keep up-to-date regarding the G4Jy Sample, 'watch' this repository: https://github.com/svw26/G4Jy",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "The Murchison Widefield Array (MWA) has observed the entire southern sky (Declination, $\\delta <$ 30 deg) at low radio-frequencies, over the range 72-231 MHz. These observations constitute the GaLactic and Extragalactic All-sky MWA (GLEAM) Survey, and we use the extragalactic catalogue (Galactic latitude, $|b| >$ 10 deg) to define the GLEAM 4-Jy (G4Jy) Sample. This is a complete sample of the 'brightest' radio-sources ($S_{\\mathrm{151MHz}} >$ 4 Jy), the majority of which are active galactic nuclei with powerful radio-jets. Crucially, low-frequency observations allow the selection of such sources in an orientation-independent way (i.e. minimising the bias caused by Doppler boosting, inherent in high-frequency surveys). We then use higher-resolution radio images, and information at other wavelengths, to morphologically classify the brightest components in GLEAM. We also conduct cross-checks against the literature, and perform internal matching, in order to improve sample completeness (which is estimated to be $>$ 95.5%). This results in a catalogue of 1,863 sources, making the G4Jy Sample over 10 times larger than that of the revised Third Cambridge Catalogue of Radio Sources (3CRR; $S_{\\mathrm{178MHz}} >$ 10.9 Jy). Of these G4Jy sources, 78 are resolved by the MWA (Phase-I) synthesised beam ($\\sim$2 arcmin at 200 MHz), and we label 67% of the sample as 'single', 26% as 'double', 4% as 'triple', and 3% as having 'complex' morphology at $\\sim$1 GHz (45-arcsec resolution). Alongside this, our value-added catalogue provides mid-infrared source associations (subject to 6-arcsec resolution at 3.4 micron) for the radio emission, as identified through visual inspection and thorough checks against the literature. As such, the G4Jy Sample can be used as a reliable training set for cross-identification via machine-learning algorithms. [Abstract abridged for arXiv submission.]",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-04-27T19:49:09.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "definition",
      "g4jy sample",
      "higher-resolution radio images",
      "murchison widefield array",
      "extragalactic all-sky mwa"
    ],
    "tags": [
      "github project"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 57,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}