The luminosity, mass, and age distributions of compact star clusters in M83 based on Hubble Space Telescope/Wide Field Camera 3 observations

Rupali Chandar, Bradley C. Whitmore, Hwihyun Kim, Catherine Kaleida, Max Mutchler, Daniela Calzetti, Abhijit Saha, Robert O'Connell, Bruce Balick, Howard Bond, Marcella Carollo, Michael Disney, Michael A. Dopita, Jay A. Frogel, Donald Hall, Jon A. Holtzman, Randy A. Kimble, Patrick McCarthy, Francesco Paresc, Joe SilkJohn Trauger, Alistair R. Walker, Rogier Windhorst, Erick Young

Research output: Contribution to journalArticle

86 Scopus citations

Abstract

The newly installed Wide Field Camera 3 (WFC3) on the Hubble Space Telescope has been used to obtain multiband images of the nearby spiral galaxy M83. These new observations are the deepest and highest resolution images ever taken of a grand-design spiral, particularly in the near-ultraviolet, and allow us to better differentiate compact star clusters from individual stars and to measure the luminosities of even faint clusters in the U band. We find that the luminosity function (LF) for clusters outside of the very crowded starburst nucleus can be approximated by a power law, dN/dL ∝ Lα, with α =-2.04 ± 0.08, down to MV ≈-5.5. We test the sensitivity of the LF to different selection techniques, filters, binning, and aperture correction determinations, and find that none of these contribute significantly to uncertainties in α. We estimate ages and masses for the clusters by comparing their measured UBVI, Hα colors with predictions from single stellar population models. The age distribution of the clusters can be approximated by a power law, dN/dτ ∝ τγ, with γ =-0.9 ± 0.2, for M ≳ few × 103 M and τ ≲ 4 × 108 yr. This indicates that clusters are disrupted quickly, with ≈80%-90% disrupted each decade in age over this time. The mass function of clusters over the same M-τ range is a power law, dN/dM ∝ Mβ, with β =-1.94 ± 0.16, and does not have bends or show curvature at either high or low masses. Therefore, we do not find evidence for a physical upper mass limit, MC, or for the earlier disruption of lower mass clusters when compared with higher mass clusters, i.e., mass-dependent disruption. We briefly discuss these implications for the formation and disruption of the clusters.

Original languageEnglish (US)
Pages (from-to)966-978
Number of pages13
JournalAstrophysical Journal
Volume719
Issue number1
DOIs
StatePublished - Oct 8 2010

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Keywords

  • Galaxies: Individual (M83), galaxies: Star clusters: General
  • Stars: Formation

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Chandar, R., Whitmore, B. C., Kim, H., Kaleida, C., Mutchler, M., Calzetti, D., Saha, A., O'Connell, R., Balick, B., Bond, H., Carollo, M., Disney, M., Dopita, M. A., Frogel, J. A., Hall, D., Holtzman, J. A., Kimble, R. A., McCarthy, P., Paresc, F., ... Young, E. (2010). The luminosity, mass, and age distributions of compact star clusters in M83 based on Hubble Space Telescope/Wide Field Camera 3 observations. Astrophysical Journal, 719(1), 966-978. https://doi.org/10.1088/0004-637X/719/1/966