Please note that eDoc will be permanently shut down in the first quarter of 2021!      Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Home
Search
Quick Search
Advanced
Fulltext
Browse
Collections
Persons
My eDoc
Session History
Login
Name:
Password:
Documentation
Help
Support Wiki
Direct access to
document ID:


          Institute: MPI für Astronomie     Collection: Publikationen_mpia     Display Documents



ID: 661045.0, MPI für Astronomie / Publikationen_mpia
The morphologies of massive galaxies at 1<z<3 in the CANDELS-UDS Field: compact bulges, and the rise and fall of massive discs
Authors:Bruce, V. A.; Dunlop, J. S.; Cirasuolo, M.; McLure, R. J.; Targett, T. A.; Bell, E. F.; Croton, D. J.; Dekel, A.; Faber, S. M.; Ferguson, H. C.; Grogin, N. A.; Kocevski, D. D.; Koekemoer, A. M.; Koo, D. C.; Lai, K.; Lotz, J. M.; McGrath, E. J.; Newman, J. A.; van der Wel, A.
Date of Publication (YYYY-MM-DD):2012
Journal Abbrev.:Monthly Notices of the Royal Astronomical Society
Volume:427
Issue / Number:2
Start Page:1666
End Page:1701
Audience:Not Specified
Abstract / Description: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.
Free Keywords:Astrophysics - Cosmology and Extragalactic Astrophysics
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI für Astronomie
Identifiers:URL:http://cdsads.u-strasbg.fr/abs/2012arXiv1206.4322B
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.