{
  "id": "2106.06544",
  "version": "v1",
  "published": "2021-06-11T18:00:00.000Z",
  "updated": "2021-06-11T18:00:00.000Z",
  "title": "The Physical Properties of Luminous $z\\gtrsim8$ Galaxies and Implications for the Cosmic Star Formation Rate Density From ~0.35 deg$^{2}$ of (Pure-)Parallel HST Observations",
  "authors": [
    "Guido Roberts-Borsani",
    "Takahiro Morishita",
    "Tommaso Treu",
    "Nicha Leethochawalit",
    "Michele Trenti"
  ],
  "comment": "29 pages, 13 figures, 8 tables. Submitted to ApJ",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "We present the largest systematic search to date for luminous $z\\gtrsim8$ galaxy candidates using ~1267 arcmin$^{2}$ of (pure-)parallel HST observations from the SuperBoRG data set, a compilation of 316 random sightlines with ACS and WFC3 observations, which together represent a factor ~1.4x larger than existing data sets. Using NIR color cuts and careful photo-$z$ analyses, we find 49 $z\\sim8-12$ galaxy candidates over 44 unique sightlines, and derive global galaxy properties such as UV magnitudes and continuum slopes, sizes, and rest-frame optical properties (e.g., SFRs, stellar masses, $A_{\\rm v}$). Taking advantage of the (pure-)parallel nature of our data set - making it one of the most representative thus far - and derived SFRs, we evaluate the cosmic star formation rate density for the bright end of the luminosity at $z\\sim8-10$ and test the validity of luminosity function-derived results using a conversion factor. We find our method yields comparable results to those derived with luminosity functions. Furthermore, we present follow up observations of 4 (Super)BoRG targets with Keck/MOSFIRE, finding no evidence of Ly$\\alpha$ in >3 hrs of $Y-$band observations in either, consistent with a largely neutral medium at $z\\sim8$. Our results offer a definitive HST legacy on the bright end of the luminosity function and provide a valuable benchmark as well as targets for follow up with JWST.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-06-11T18:00:00.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "cosmic star formation rate density",
      "parallel hst observations",
      "physical properties",
      "data set"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 29,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}