Galaxy merger histories and the role of merging in driving star formation at z > 1
<p>We use Horizon-AGN, a hydrodynamical cosmological simulation, to explore the role of mergers in the evolution of massive (<em>M</em><sub>*</sub> > 10<sup>10</sup> M<sub>⊙</sub>) galaxies around the epoch of peak cosmic star formation (...
| Hoofdauteurs: | , , , , , , , |
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| Formaat: | Journal article |
| Gepubliceerd in: |
Oxford University Press
2015
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| _version_ | 1826294137042763776 |
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| author | Kaviraj, S Devriendt, J Dubois, Y Slyz, A Welker, C Pichon, C Peirani, S Borgne, D |
| author_facet | Kaviraj, S Devriendt, J Dubois, Y Slyz, A Welker, C Pichon, C Peirani, S Borgne, D |
| author_sort | Kaviraj, S |
| collection | OXFORD |
| description | <p>We use Horizon-AGN, a hydrodynamical cosmological simulation, to explore the role of mergers in the evolution of massive (<em>M</em><sub>*</sub> > 10<sup>10</sup> M<sub>⊙</sub>) galaxies around the epoch of peak cosmic star formation (1 < <em>z</em> < 4). The fraction of massive galaxies in major mergers (mass ratio <em>R</em> < 4: 1) is around 3 per cent, a factor of ∼2.5 lower than minor mergers (4: 1 < <em>R</em> < 10: 1) at these epochs, with no trend with redshift. At <em>z</em> ∼ 1, around a third of massive galaxies have undergone a major merger, while all remaining systems have undergone a minor merger. While almost all major mergers at <em>z</em> > 3 are ‘blue’ (i.e. have significant associated star formation), the proportion of ‘red’ mergers increases rapidly at <em>z</em> < 2, with most merging systems at <em>z</em> ∼ 1.5 producing remnants that are red in rest-frame UV–optical colours. The star formation enhancement during major mergers is mild (∼20–40 per cent) which, together with the low incidence of such events, implies that this process is not a significant driver of early stellar mass growth. Mergers (<em>R</em> < 10: 1) host around a quarter of the total star formation budget in this redshift range, with major mergers hosting around two-thirds of this contribution. Notwithstanding their central importance to the standard Λ cold dark matter paradigm, mergers are minority players in driving star formation at the epochs where the bulk of today's stellar mass was formed.</p> |
| first_indexed | 2024-03-07T03:40:59Z |
| format | Journal article |
| id | oxford-uuid:bde2a97c-ad0b-4e13-bdc9-e4695461b9ae |
| institution | University of Oxford |
| last_indexed | 2024-03-07T03:40:59Z |
| publishDate | 2015 |
| publisher | Oxford University Press |
| record_format | dspace |
| spelling | oxford-uuid:bde2a97c-ad0b-4e13-bdc9-e4695461b9ae2022-03-27T05:35:09Z Galaxy merger histories and the role of merging in driving star formation at z > 1 Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:bde2a97c-ad0b-4e13-bdc9-e4695461b9aeSymplectic Elements at OxfordOxford University Press2015Kaviraj, SDevriendt, JDubois, YSlyz, AWelker, CPichon, CPeirani, SBorgne, D <p>We use Horizon-AGN, a hydrodynamical cosmological simulation, to explore the role of mergers in the evolution of massive (<em>M</em><sub>*</sub> > 10<sup>10</sup> M<sub>⊙</sub>) galaxies around the epoch of peak cosmic star formation (1 < <em>z</em> < 4). The fraction of massive galaxies in major mergers (mass ratio <em>R</em> < 4: 1) is around 3 per cent, a factor of ∼2.5 lower than minor mergers (4: 1 < <em>R</em> < 10: 1) at these epochs, with no trend with redshift. At <em>z</em> ∼ 1, around a third of massive galaxies have undergone a major merger, while all remaining systems have undergone a minor merger. While almost all major mergers at <em>z</em> > 3 are ‘blue’ (i.e. have significant associated star formation), the proportion of ‘red’ mergers increases rapidly at <em>z</em> < 2, with most merging systems at <em>z</em> ∼ 1.5 producing remnants that are red in rest-frame UV–optical colours. The star formation enhancement during major mergers is mild (∼20–40 per cent) which, together with the low incidence of such events, implies that this process is not a significant driver of early stellar mass growth. Mergers (<em>R</em> < 10: 1) host around a quarter of the total star formation budget in this redshift range, with major mergers hosting around two-thirds of this contribution. Notwithstanding their central importance to the standard Λ cold dark matter paradigm, mergers are minority players in driving star formation at the epochs where the bulk of today's stellar mass was formed.</p> |
| spellingShingle | Kaviraj, S Devriendt, J Dubois, Y Slyz, A Welker, C Pichon, C Peirani, S Borgne, D Galaxy merger histories and the role of merging in driving star formation at z > 1 |
| title |
Galaxy merger histories and the role of merging in driving star formation at z > 1
|
| title_full |
Galaxy merger histories and the role of merging in driving star formation at z > 1
|
| title_fullStr |
Galaxy merger histories and the role of merging in driving star formation at z > 1
|
| title_full_unstemmed |
Galaxy merger histories and the role of merging in driving star formation at z > 1
|
| title_short |
Galaxy merger histories and the role of merging in driving star formation at z > 1
|
| title_sort | galaxy merger histories and the role of merging in driving star formation at z gt 1 |
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