Galaxy Zoo: star-formation versus spiral arm number
Spiral arms are common features in low-redshift disc galaxies, and are prominent sites of star-formation and dust obscuration. However, spiral structure can take many forms: from galaxies displaying two strong `grand design' arms, to those with many `flocculent' arms. We investigate how th...
| Main Authors: | , , , , , |
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| Format: | Journal article |
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Oxford University Press
2017
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| _version_ | 1797074964337131520 |
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| author | Hart, R Bamford, S Casteels, K Kruk, S Lintott, C Masters, K |
| author_facet | Hart, R Bamford, S Casteels, K Kruk, S Lintott, C Masters, K |
| author_sort | Hart, R |
| collection | OXFORD |
| description | Spiral arms are common features in low-redshift disc galaxies, and are prominent sites of star-formation and dust obscuration. However, spiral structure can take many forms: from galaxies displaying two strong `grand design' arms, to those with many `flocculent' arms. We investigate how these different arm types are related to a galaxy's star-formation and gas properties by making use of visual spiral arm number measurements from Galaxy Zoo 2. We combine UV and mid-IR photometry from GALEX and WISE to measure the rates and relative fractions of obscured and unobscured star formation in a sample of low-redshift SDSS spirals. Total star formation rate has little dependence on spiral arm multiplicity, but two-armed spirals convert their gas to stars more efficiently. We find significant differences in the fraction of obscured star-formation: an additional $\sim 10$ per cent of star-formation in two-armed galaxies is identified via mid-IR dust emission, compared to that in many-armed galaxies. The latter are also significantly offset below the IRX-$\beta$ relation for low-redshift star-forming galaxies. We present several explanations for these differences versus arm number: variations in the spatial distribution, sizes or clearing timescales of star-forming regions (i.e., molecular clouds), or contrasting recent star-formation histories. |
| first_indexed | 2024-03-06T23:43:47Z |
| format | Journal article |
| id | oxford-uuid:7035e0a8-7810-40da-8d02-563f0bce08e2 |
| institution | University of Oxford |
| last_indexed | 2024-03-06T23:43:47Z |
| publishDate | 2017 |
| publisher | Oxford University Press |
| record_format | dspace |
| spelling | oxford-uuid:7035e0a8-7810-40da-8d02-563f0bce08e22022-03-26T19:35:41ZGalaxy Zoo: star-formation versus spiral arm numberJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:7035e0a8-7810-40da-8d02-563f0bce08e2Symplectic Elements at OxfordOxford University Press2017Hart, RBamford, SCasteels, KKruk, SLintott, CMasters, KSpiral arms are common features in low-redshift disc galaxies, and are prominent sites of star-formation and dust obscuration. However, spiral structure can take many forms: from galaxies displaying two strong `grand design' arms, to those with many `flocculent' arms. We investigate how these different arm types are related to a galaxy's star-formation and gas properties by making use of visual spiral arm number measurements from Galaxy Zoo 2. We combine UV and mid-IR photometry from GALEX and WISE to measure the rates and relative fractions of obscured and unobscured star formation in a sample of low-redshift SDSS spirals. Total star formation rate has little dependence on spiral arm multiplicity, but two-armed spirals convert their gas to stars more efficiently. We find significant differences in the fraction of obscured star-formation: an additional $\sim 10$ per cent of star-formation in two-armed galaxies is identified via mid-IR dust emission, compared to that in many-armed galaxies. The latter are also significantly offset below the IRX-$\beta$ relation for low-redshift star-forming galaxies. We present several explanations for these differences versus arm number: variations in the spatial distribution, sizes or clearing timescales of star-forming regions (i.e., molecular clouds), or contrasting recent star-formation histories. |
| spellingShingle | Hart, R Bamford, S Casteels, K Kruk, S Lintott, C Masters, K Galaxy Zoo: star-formation versus spiral arm number |
| title | Galaxy Zoo: star-formation versus spiral arm number |
| title_full | Galaxy Zoo: star-formation versus spiral arm number |
| title_fullStr | Galaxy Zoo: star-formation versus spiral arm number |
| title_full_unstemmed | Galaxy Zoo: star-formation versus spiral arm number |
| title_short | Galaxy Zoo: star-formation versus spiral arm number |
| title_sort | galaxy zoo star formation versus spiral arm number |
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