Star cluster catalogues for the LEGUS dwarf galaxies
Affiliation
Univ Arizona, Steward Observ, Dept AstronIssue Date
2019-04Keywords
galaxies: dwarfgalaxies: irregular
Local Group
galaxies: photometry
galaxies: star clusters: general
galaxies: spiral
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OXFORD UNIV PRESSCitation
D O Cook, J C Lee, A Adamo, H Kim, R Chandar, B C Whitmore, A Mok, J E Ryon, D A Dale, D Calzetti, J E Andrews, A Aloisi, G Ashworth, S N Bright, T M Brown, C Christian, M Cignoni, G C Clayton, R da Silva, S E de Mink, C L Dobbs, B G Elmegreen, D M Elmegreen, A S Evans, M Fumagalli, J S Gallagher, D A Gouliermis, K Grasha, E K Grebel, A Herrero, D A Hunter, E I Jensen, K E Johnson, L Kahre, R C Kennicutt, M R Krumholz, N J Lee, D Lennon, S Linden, C Martin, M Messa, P Nair, A Nota, G Östlin, R C Parziale, A Pellerin, M W Regan, E Sabbi, E Sacchi, D Schaerer, D Schiminovich, F Shabani, F A Slane, J Small, C L Smith, L J Smith, S Taibi, D A Thilker, I C de la Torre, M Tosi, J A Turner, L Ubeda, S D Van Dyk, R AM Walterbos, A Wofford, Star cluster catalogues for the LEGUS dwarf galaxies, Monthly Notices of the Royal Astronomical Society, Volume 484, Issue 4, April 2019, Pages 4897–4919, https://doi.org/10.1093/mnras/stz331Rights
© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical SocietyCollection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
We present the star cluster catalogues for 17 dwarf and irregular galaxies in the HST Treasury Program 'Legacy ExtraGalactic UV Survey' (LEGUS). Cluster identification and photometry in this sub-sample are similar to that of the entire LEGUS sample, but special methods were developed to provide robust catalogues with accurate fluxes due to low cluster statistics. The colours and ages are largely consistent for two widely used aperture corrections, but a significant fraction of the clusters are more compact than the average training cluster. However, the ensemble luminosity, mass, and age distributions are consistent suggesting that the systematics between the two methods are less than the random errors. When compared with the clusters from previous dwarf galaxy samples, we find that the LEGUS catalogues are more complete and provide more accurate total fluxes. Combining all clusters into a composite dwarf galaxy, we find that the luminosity and mass functions can be described by a power law with the canonical index of -2 independent of age and global SFR binning. The age distribution declines as a power law, with an index of approximate to -0.80 +/- 0.15, independent of cluster mass and global SFR binning. This decline of clusters is dominated by cluster disruption since the combined star formation histories and integrated-light SFRs are both approximately constant over the last few hundred Myr. Finally, we find little evidence for an upper-mass cut-off (< 2 sigma) in the composite cluster mass function, and can rule out a truncation mass below approximate to 10(4.5)M(circle dot) but cannot rule out the existence of a truncation at higher masses.ISSN
0035-87111365-2966
Version
Final published versionSponsors
NASA [NAS 5-26555]; NASA; Swedish Research Council (Vetenskapsradet); Swedish National Space Board (SNSB); German Aerospace Center (DLR); Federal Ministry for EconomicAffairs and Energy (BMWi) [50OR1801]; [13364]Additional Links
https://academic.oup.com/mnras/article/484/4/4897/5305866Scopus Count
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