LESS THAN 10 PERCENT OF STAR FORMATION IN z similar to 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS
Both observations and simulations show that major tidal interactions or mergers between gas-rich galaxies can lead to intense bursts of star formation. Yet, the average enhancement in star formation rate (SFR) in major mergers and the contribution of such events to the cosmic SFR are not well estima...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
Institute of Physics Publishing
2009
|
| _version_ | 1797098109384261632 |
|---|---|
| author | Robaina, A Bell, E Skelton, R McIntosh, D Somerville, R Zheng, X Rix, H Bacon, D Balogh, M Barazza, F Barden, M Boehm, A Caldwell, J Gallazzi, A Gray, M Haeussler, B Heymans, C Jahnke, K Jogee, S van Kampen, E Lane, K Meisenheimer, K Papovich, C Peng, C Sanchez, S |
| author_facet | Robaina, A Bell, E Skelton, R McIntosh, D Somerville, R Zheng, X Rix, H Bacon, D Balogh, M Barazza, F Barden, M Boehm, A Caldwell, J Gallazzi, A Gray, M Haeussler, B Heymans, C Jahnke, K Jogee, S van Kampen, E Lane, K Meisenheimer, K Papovich, C Peng, C Sanchez, S |
| author_sort | Robaina, A |
| collection | OXFORD |
| description | Both observations and simulations show that major tidal interactions or mergers between gas-rich galaxies can lead to intense bursts of star formation. Yet, the average enhancement in star formation rate (SFR) in major mergers and the contribution of such events to the cosmic SFR are not well estimated. Here we use photometric redshifts, stellar masses, and UV SFRs from COMBO-17, 24 μm SFRs from Spitzer, and morphologies from two deep Hubble Space Telescope (HST) cosmological survey fields (ECDFS/GEMS and A901/STAGES) to study the enhancement in SFR as a function of projected galaxy separation. We apply two-point projected correlation function techniques, which we augment with morphologically selected very close pairs (separation <2″) and merger remnants from the HST imaging. Our analysis confirms that the most intensely star-forming systems are indeed interacting or merging. Yet, for massive (M * ≥ 1010 M ⊙) star-forming galaxies at 0.4 < z < 0.8, we find that the SFRs of galaxies undergoing a major interaction (mass ratios ≤1:4 and separations ≤40 kpc) are only 1.80 ± 0.30 times higher than the SFRs of non-interacting galaxies when averaged over all interactions and all stages of the interaction, in good agreement with other observational works. Our results also agree with hydrodynamical simulations of galaxy interactions, which produce some mergers with large bursts of star formation on 100 Myr timescales, but only a modest SFR enhancement when averaged over the entire merger timescale. We demonstrate that these results imply that only ≲10% of star formation at 0.4 ≤ z ≤ 0.8 is triggered directly by major mergers and interactions; these events are not important factors in the build-up of stellar mass since z = 1. © 2009. The American Astronomical Society. All rights reserved.. |
| first_indexed | 2024-03-07T05:04:57Z |
| format | Journal article |
| id | oxford-uuid:d99aa2e8-0851-4e7e-a0c4-de0b4c38d483 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T05:04:57Z |
| publishDate | 2009 |
| publisher | Institute of Physics Publishing |
| record_format | dspace |
| spelling | oxford-uuid:d99aa2e8-0851-4e7e-a0c4-de0b4c38d4832022-03-27T08:57:05ZLESS THAN 10 PERCENT OF STAR FORMATION IN z similar to 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONSJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:d99aa2e8-0851-4e7e-a0c4-de0b4c38d483EnglishSymplectic Elements at OxfordInstitute of Physics Publishing2009Robaina, ABell, ESkelton, RMcIntosh, DSomerville, RZheng, XRix, HBacon, DBalogh, MBarazza, FBarden, MBoehm, ACaldwell, JGallazzi, AGray, MHaeussler, BHeymans, CJahnke, KJogee, Svan Kampen, ELane, KMeisenheimer, KPapovich, CPeng, CSanchez, SBoth observations and simulations show that major tidal interactions or mergers between gas-rich galaxies can lead to intense bursts of star formation. Yet, the average enhancement in star formation rate (SFR) in major mergers and the contribution of such events to the cosmic SFR are not well estimated. Here we use photometric redshifts, stellar masses, and UV SFRs from COMBO-17, 24 μm SFRs from Spitzer, and morphologies from two deep Hubble Space Telescope (HST) cosmological survey fields (ECDFS/GEMS and A901/STAGES) to study the enhancement in SFR as a function of projected galaxy separation. We apply two-point projected correlation function techniques, which we augment with morphologically selected very close pairs (separation <2″) and merger remnants from the HST imaging. Our analysis confirms that the most intensely star-forming systems are indeed interacting or merging. Yet, for massive (M * ≥ 1010 M ⊙) star-forming galaxies at 0.4 < z < 0.8, we find that the SFRs of galaxies undergoing a major interaction (mass ratios ≤1:4 and separations ≤40 kpc) are only 1.80 ± 0.30 times higher than the SFRs of non-interacting galaxies when averaged over all interactions and all stages of the interaction, in good agreement with other observational works. Our results also agree with hydrodynamical simulations of galaxy interactions, which produce some mergers with large bursts of star formation on 100 Myr timescales, but only a modest SFR enhancement when averaged over the entire merger timescale. We demonstrate that these results imply that only ≲10% of star formation at 0.4 ≤ z ≤ 0.8 is triggered directly by major mergers and interactions; these events are not important factors in the build-up of stellar mass since z = 1. © 2009. The American Astronomical Society. All rights reserved.. |
| spellingShingle | Robaina, A Bell, E Skelton, R McIntosh, D Somerville, R Zheng, X Rix, H Bacon, D Balogh, M Barazza, F Barden, M Boehm, A Caldwell, J Gallazzi, A Gray, M Haeussler, B Heymans, C Jahnke, K Jogee, S van Kampen, E Lane, K Meisenheimer, K Papovich, C Peng, C Sanchez, S LESS THAN 10 PERCENT OF STAR FORMATION IN z similar to 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS |
| title | LESS THAN 10 PERCENT OF STAR FORMATION IN z similar to 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS |
| title_full | LESS THAN 10 PERCENT OF STAR FORMATION IN z similar to 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS |
| title_fullStr | LESS THAN 10 PERCENT OF STAR FORMATION IN z similar to 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS |
| title_full_unstemmed | LESS THAN 10 PERCENT OF STAR FORMATION IN z similar to 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS |
| title_short | LESS THAN 10 PERCENT OF STAR FORMATION IN z similar to 0.6 MASSIVE GALAXIES IS TRIGGERED BY MAJOR INTERACTIONS |
| title_sort | less than 10 percent of star formation in z similar to 0 6 massive galaxies is triggered by major interactions |
| work_keys_str_mv | AT robainaa lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT belle lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT skeltonr lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT mcintoshd lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT somerviller lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT zhengx lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT rixh lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT bacond lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT baloghm lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT barazzaf lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT bardenm lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT boehma lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT caldwellj lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT gallazzia lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT graym lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT haeusslerb lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT heymansc lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT jahnkek lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT jogees lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT vankampene lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT lanek lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT meisenheimerk lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT papovichc lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT pengc lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions AT sanchezs lessthan10percentofstarformationinzsimilarto06massivegalaxiesistriggeredbymajorinteractions |