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Ultra-Compact Dwarf Galaxies – More Massive than Allowed?

Published online by Cambridge University Press:  01 September 2007

Michael Hilker ,
S. Mieske ,
H. Baumgardt  and
J. Dabringhausen
Michael Hilker
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany email: [email protected], [email protected]
S. Mieske
Affiliation:
ESO, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany email: [email protected], [email protected]
H. Baumgardt
Affiliation:
AIfA, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany email: [email protected], [email protected]
J. Dabringhausen
Affiliation:
AIfA, Universität Bonn, Auf dem Hügel 71, 53121 Bonn, Germany email: [email protected], [email protected]
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Abstract

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Dynamical mass estimates of ultra-compact dwarfs galaxies and massive globular clusters in the Fornax and Virgo clusters and around the giant elliptical Cen A have revealed some surprising results: 1) above ~106M⊙ the mass-to-light (M/L) ratio increases with the objects' mass; 2) some UCDs/massive GCs show high M/L values (4 to 6) that are not compatible with standard stellar population models; and 3) in the luminosity-velocity dispersion diagram, UCDs deviate from the well-defined relation of “normal” GCs, being more in line with the Faber-Jackson relation of early-type galaxies. In this contribution, we present the observational evidences for high mass-to-light ratios of UCDs and discuss possible explanations for them.

Keywords

galaxies: star clustersgalaxies: dwarfgalaxies: kinematics and dynamics
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 3 , Symposium S246: Dynamical Evolution of Dense Stellar Systems , September 2007 , pp. 427 - 428
Copyright
Copyright © International Astronomical Union 2008

References

Bruzual, G. A., Charlot, S. 2003, MNRAS 344, 1000CrossRefGoogle Scholar
Drinkwater, M. J., Jones, J. B., Gregg, M. D., Phillipps, S. 2000, PASA 17, 227CrossRefGoogle Scholar
Fellhauer, M., Kroupa, P. 2006, MNRAS 367, 1577CrossRefGoogle Scholar
Hilker, M., Baumgardt, H., Infante, L., et al. 2007, A&A 463, 777Google Scholar
Hilker, M., Infante, L., Vieira, G., Kissler-Patig, M., Richtler, T. 1999, A&AS 134, 75Google Scholar
Maraston, C. 2005, MNRAS 362, 799CrossRefGoogle Scholar