Obscured star formation in intermediate-density environments: A Spitzer study of the Abell 901/902 supercluster
We explore the amount of obscured star-formation as a function of environment in the A901/902 supercluster at z=0.165 in conjunction with a field sample drawn from the A901 and CDFS fields, imaged with HST as part of the STAGES and GEMS surveys. We combine the COMBO-17 near-UV/optical SED with Spitz...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
Institute of Physics Publishing
2008
|
| _version_ | 1797082916407214080 |
|---|---|
| author | Gallazzi, A Bell, E Wolf, C Gray, M Papovich, C Barden, M Peng, C Meisenheimer, K Heymans, C Kampen, E Gilmour, R Balogh, M McIntosh, D Bacon, D Barazza, F Boehm, A Caldwell, J Haeussler, B Jahnke, K Jogee, S Lane, K Robaina, A Sanchez, S Taylor, A Wisotzki, L |
| author_facet | Gallazzi, A Bell, E Wolf, C Gray, M Papovich, C Barden, M Peng, C Meisenheimer, K Heymans, C Kampen, E Gilmour, R Balogh, M McIntosh, D Bacon, D Barazza, F Boehm, A Caldwell, J Haeussler, B Jahnke, K Jogee, S Lane, K Robaina, A Sanchez, S Taylor, A Wisotzki, L |
| author_sort | Gallazzi, A |
| collection | OXFORD |
| description | We explore the amount of obscured star-formation as a function of environment in the A901/902 supercluster at z=0.165 in conjunction with a field sample drawn from the A901 and CDFS fields, imaged with HST as part of the STAGES and GEMS surveys. We combine the COMBO-17 near-UV/optical SED with Spitzer 24um photometry to estimate both the unobscured and obscured star formation in galaxies with Mstar>10^{10}Msun. We find that the star formation activity in massive galaxies is suppressed in dense environments, in agreement with previous studies. Yet, nearly 40% of the star-forming galaxies have red optical colors at intermediate and high densities. These red systems are not starbursting; they have star formation rates per unit stellar mass similar to or lower than blue star-forming galaxies. More than half of the red star-forming galaxies have low IR-to-UV luminosity ratios, relatively high Sersic indices and they are equally abundant at all densities. They might be gradually quenching their star-formation, possibly but not necessarily under the influence of gas-removing environmental processes. The other >40% of the red star-forming galaxies have high IR-to-UV luminosity ratios, indicative of high dust obscuration. They have relatively high specific star formation rates and are more abundant at intermediate densities. Our results indicate that while there is an overall suppression in the star-forming galaxy fraction with density, the small amount of star formation surviving the cluster environment is to a large extent obscured, suggesting that environmental interactions trigger a phase of obscured star formation, before complete quenching. |
| first_indexed | 2024-03-07T01:34:41Z |
| format | Journal article |
| id | oxford-uuid:94bd8bc7-debd-4e88-bfba-75a5e500c263 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T01:34:41Z |
| publishDate | 2008 |
| publisher | Institute of Physics Publishing |
| record_format | dspace |
| spelling | oxford-uuid:94bd8bc7-debd-4e88-bfba-75a5e500c2632022-03-26T23:41:36ZObscured star formation in intermediate-density environments: A Spitzer study of the Abell 901/902 superclusterJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:94bd8bc7-debd-4e88-bfba-75a5e500c263EnglishSymplectic Elements at OxfordInstitute of Physics Publishing2008Gallazzi, ABell, EWolf, CGray, MPapovich, CBarden, MPeng, CMeisenheimer, KHeymans, CKampen, EGilmour, RBalogh, MMcIntosh, DBacon, DBarazza, FBoehm, ACaldwell, JHaeussler, BJahnke, KJogee, SLane, KRobaina, ASanchez, STaylor, AWisotzki, LWe explore the amount of obscured star-formation as a function of environment in the A901/902 supercluster at z=0.165 in conjunction with a field sample drawn from the A901 and CDFS fields, imaged with HST as part of the STAGES and GEMS surveys. We combine the COMBO-17 near-UV/optical SED with Spitzer 24um photometry to estimate both the unobscured and obscured star formation in galaxies with Mstar>10^{10}Msun. We find that the star formation activity in massive galaxies is suppressed in dense environments, in agreement with previous studies. Yet, nearly 40% of the star-forming galaxies have red optical colors at intermediate and high densities. These red systems are not starbursting; they have star formation rates per unit stellar mass similar to or lower than blue star-forming galaxies. More than half of the red star-forming galaxies have low IR-to-UV luminosity ratios, relatively high Sersic indices and they are equally abundant at all densities. They might be gradually quenching their star-formation, possibly but not necessarily under the influence of gas-removing environmental processes. The other >40% of the red star-forming galaxies have high IR-to-UV luminosity ratios, indicative of high dust obscuration. They have relatively high specific star formation rates and are more abundant at intermediate densities. Our results indicate that while there is an overall suppression in the star-forming galaxy fraction with density, the small amount of star formation surviving the cluster environment is to a large extent obscured, suggesting that environmental interactions trigger a phase of obscured star formation, before complete quenching. |
| spellingShingle | Gallazzi, A Bell, E Wolf, C Gray, M Papovich, C Barden, M Peng, C Meisenheimer, K Heymans, C Kampen, E Gilmour, R Balogh, M McIntosh, D Bacon, D Barazza, F Boehm, A Caldwell, J Haeussler, B Jahnke, K Jogee, S Lane, K Robaina, A Sanchez, S Taylor, A Wisotzki, L Obscured star formation in intermediate-density environments: A Spitzer study of the Abell 901/902 supercluster |
| title | Obscured star formation in intermediate-density environments: A Spitzer
study of the Abell 901/902 supercluster |
| title_full | Obscured star formation in intermediate-density environments: A Spitzer
study of the Abell 901/902 supercluster |
| title_fullStr | Obscured star formation in intermediate-density environments: A Spitzer
study of the Abell 901/902 supercluster |
| title_full_unstemmed | Obscured star formation in intermediate-density environments: A Spitzer
study of the Abell 901/902 supercluster |
| title_short | Obscured star formation in intermediate-density environments: A Spitzer
study of the Abell 901/902 supercluster |
| title_sort | obscured star formation in intermediate density environments a spitzer study of the abell 901 902 supercluster |
| work_keys_str_mv | AT gallazzia obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT belle obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT wolfc obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT graym obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT papovichc obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT bardenm obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT pengc obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT meisenheimerk obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT heymansc obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT kampene obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT gilmourr obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT baloghm obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT mcintoshd obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT bacond obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT barazzaf obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT boehma obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT caldwellj obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT haeusslerb obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT jahnkek obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT jogees obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT lanek obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT robainaa obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT sanchezs obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT taylora obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster AT wisotzkil obscuredstarformationinintermediatedensityenvironmentsaspitzerstudyoftheabell901902supercluster |