High M/L ratios of UCDs: a variation of the IMF?

Abstract

Various studies have established that the dynamical M/L ratios of ultra-compact dwarf galaxies (UCDs) tend to be at the limit or beyond the range explicable by standard stellar populations with canonical IMF. We discuss how IMF variations may account for these high M/L ratios and how observational approaches may in the future allow to discriminate between those possibilities. We also briefly discuss the possibility of dark matter in UCDs.

arXiv comment4 pages, 4 figures, contribution to the conference "Galactic and Stellar Dynamics in the Era of High Resolution Surveys", 16-20 March 2008, Strasbourg. Eds. C. Boily, F. Combes, G. Hensler. 2nd version includes 2 new references

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Cited by in corpus (7)

• The Ubiquity and Dual Nature of Ultra Compact Dwarfs
• The AIMSS Project III: The Stellar Populations of Compact Stellar Systems
• Ultra-Compact Dwarfs in the Coma Cluster
• The formation of UCDs and massive GCs: Quasar-like objects for testing for a variable stellar initial mass function (IMF)
• The AIMSS Project II: Dynamical-to-Stellar Mass Ratios Across the Star Cluster - Galaxy Divide
• How elevated is the dynamical-to-stellar mass ratio of the ultra-compact dwarf S999?
• A search for active galactic nuclei in low-mass compact galaxies