Journal article
The role of mergers in driving morphological transformation over cosmic time
- Abstract:
- Understanding the processes that trigger morphological transformation is central to understanding how and why the Universe transitions from being disc-dominated at early epochs to having the morphological mix that is observed today. We use Horizon-AGN, a cosmological hydrodynamical simulation, to perform a comprehensive study of the processes that drive morphological change in massive (M > 10^10 MSun) galaxies over cosmic time. We show that (1) essentially all the morphological evolution in galaxies that are spheroids at z=0 is driven by mergers with mass ratios greater than 1:10, (2) major mergers alone cannot produce today's spheroid population -- minor mergers are responsible for a third of all morphological transformation over cosmic time and are its dominant driver after z~1, (3) prograde mergers trigger milder morphological transformation than retrograde mergers -- while both types of events produce similar morphological changes at z>2, the average change due to retrograde mergers is around twice that due to their prograde counterparts at z~0, (4) remnant morphology depends strongly on the gas fraction of a merger, with gas-rich mergers routinely re-growing discs, and (5) at a given stellar mass, discs do not exhibit drastically different merger histories from spheroids -- disc survival in mergers is driven by acquisition of cold gas (via cosmological accretion and gas-rich interactions) and a preponderance of prograde mergers in their merger histories.
- Publication status:
- Published
- Peer review status:
- Peer reviewed
Actions
Access Document
- Files:
-
-
(Preview, Version of record, pdf, 2.5MB, Terms of use)
-
- Publisher copy:
- 10.1093/mnras/sty1936
Authors
+ Science and Technology Facilities Council
More from this funder
- Funding agency for:
- Devriendt, J
- Grant:
- ST/N504105/1
- Publisher:
- Oxford University Press
- Journal:
- Monthly Notices of the Royal Astronomical Society More from this journal
- Volume:
- 480
- Issue:
- 2
- Pages:
- 2266–2283
- Publication date:
- 2018-07-24
- Acceptance date:
- 2018-07-17
- DOI:
- EISSN:
-
1365-2966
- ISSN:
-
0035-8711
- Keywords:
- Pubs id:
-
pubs:891646
- UUID:
-
uuid:e1f4550f-01f4-4d0a-81b0-53d3be342c8a
- Local pid:
-
pubs:891646
- Source identifiers:
-
891646
- Deposit date:
-
2018-09-13
Terms of use
- Copyright holder:
- Martin et al
- Copyright date:
- 2018
- Notes:
- © The Author(s) 2018. Published by Oxford University Press on behalf of The Royal Astronomical Society This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
- Licence:
- CC Attribution (CC BY)
If you are the owner of this record, you can report an update to it here: Report update to this record