{
  "id": "1206.4322",
  "version": "v1",
  "published": "2012-06-19T20:00:23.000Z",
  "updated": "2012-06-19T20:00:23.000Z",
  "title": "The Morphologies of Massive Galaxies at 1<z<3 in the CANDELS-UDS Field: Compact Bulges, and the Rise and Fall of Massive Disks",
  "authors": [
    "V. A. Bruce",
    "J. S. Dunlop",
    "M. Cirasuolo",
    "R. J. McLure",
    "T. A. Targett",
    "E. F. Bell",
    "D. J. Croton",
    "A. Dekel",
    "S. M. Faber",
    "H. C. Ferguson",
    "N. A. Grogin",
    "D. D. Kocevski",
    "A. M. Koekemoer",
    "D. C. Koo",
    "K. Lai",
    "J. M. Lotz",
    "E. J. McGrath",
    "J. A. Newman",
    "A. van der Wel"
  ],
  "comment": "39 pages, 19 figures, 2 tables, submitted to MNRAS",
  "categories": [
    "astro-ph.CO"
  ],
  "abstract": "We have used deep, HST, near-IR imaging to study the morphological properties of the most massive galaxies at high z, modelling the WFC3/IR H-band images of the ~200 galaxies in the CANDELS-UDS field with 1 < z_phot < 3, and stellar masses M_star > 10^11 M_sun. We have used both single-Sersic and bulge+disk models, have investigated the errors/biases introduced by uncertainties in the background and the PSF, and have obtained formally-acceptable model fits to >90% of the galaxies. Our results indicate that these massive galaxies at 1 < z < 3 lie both on and below the local size-mass relation, with a median R_e~2.6 kpc, a factor of ~2.3 smaller than comparably-massive local galaxies. Moreover, we find that bulge-dominated objects in particular show evidence for a growing bimodality in the size-mass relation with increasing z, and by z > 2 the compact bulges display effective radii a factor ~4 smaller than local ellipticals of comparable mass. These trends appear to extend to the bulge components of disk-dominated galaxies, and vice versa. We also find that, while such massive galaxies at low z are bulge-dominated, at 1 < z < 2 they are predominantly mixed bulge+disk systems, and by z > 2 they are mostly disk-dominated. The majority of the disk-dominated galaxies are actively forming stars, but this is also true for many of the bulge-dominated systems. Interestingly, however, while most of the quiescent galaxies are bulge-dominated, we find that a significant fraction (25-40%) of the most quiescent galaxies have disk-dominated morphologies. Thus, while our results show that the massive galaxy population is undergoing dramatic changes at this crucial epoch, they also suggest that the physical mechanisms which quench star-formation activity are not simply connected to those responsible for the morphological transformation of massive galaxies into present-day giant ellipticals.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2012-06-19T20:00:23.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "massive galaxy",
      "candels-uds field",
      "massive disks",
      "morphologies",
      "quiescent galaxies"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1111/j.1365-2966.2012.22087.x",
      "journal": "Monthly Notices of the Royal Astronomical Society",
      "year": 2012,
      "month": "Dec",
      "volume": 427,
      "number": 2,
      "pages": 1666
    },
    "note": {
      "typesetting": "TeX",
      "pages": 39,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1118796,
      "adsabs": "2012MNRAS.427.1666B"
    }
  }
}