콜로퀴움
[KASI-CNU Joint Colloquium] An introduction to ESO and news on ultra-compact dwarf galaxies 2015-09-16
- Speaker : Dr. Michael Hilker (European Southern Observatory)
- Date : 2015-09-16 16:00 ~ 17:30
- Location : J331-2
- Host : Dr. Chang Hee Ree
The European Southern Observatory (ESO) is an intergovernmental astronomy
organisation that provides state-of-the-art research facilities in Chile to
astronomers in Europe and all over the world. Engineers, administrative staff,
astronomers, scientists and many more, based in Chile and Germany, work
together to keep ESO one of the world's most productive astronomical
observatories. ESO astronomers are also very active in their own research
fields, covering topics from exoplanets to high-redshift cosmology.
I will give a brief introduction about the current activities of ESO and will
highlight how ESO astronomers manage to combine their functional work with
conducting forefront science.
In the second part of my presentation, I will focus on my own scientific
work. More than 16 years ago, so-called 'Ultra-Compact Dwarf galaxies' (UCDs)
have been discovered in spectroscopic surveys of the Fornax galaxy cluster
by our team. UCDs have a special place in the fundamental plane of pressure
supported stellar systems. They are located at the high mass end of the
globular cluster (GC) distribution, reaching ~10^8 M_sun and obey a mass-size
relation unlike 'classical' GCs, but connecting to compact ellipticals.
Nowadays, dozens, if not hundreds, of UCDs and their fellow `dwarf galaxy
transition objects' (DGTOs), `giant globular clusters' (GGCs) and `extended
clusters' (ECs) have been identified in various environments, filling the
space in the fundamental plane between star clusters and dwarf galaxies.
I will review the knowledge we obtained over the last 16 years of these
sometimes still puzzling objects. I will present the occurence, spatial
distribution, dynamics and mass spectrum of UCDs in different environments.
For some of the bright UCDs, internal properties (metallicity, ages,
[alpha/Fe] abundances, internal kinematics, clues to their IMF, etc.) are
available, which I will highlight. Finally, I will summarize our current
ideas about their formation and will conclude that the majority of UCDs
belong to the 'star cluster family'.
organisation that provides state-of-the-art research facilities in Chile to
astronomers in Europe and all over the world. Engineers, administrative staff,
astronomers, scientists and many more, based in Chile and Germany, work
together to keep ESO one of the world's most productive astronomical
observatories. ESO astronomers are also very active in their own research
fields, covering topics from exoplanets to high-redshift cosmology.
I will give a brief introduction about the current activities of ESO and will
highlight how ESO astronomers manage to combine their functional work with
conducting forefront science.
In the second part of my presentation, I will focus on my own scientific
work. More than 16 years ago, so-called 'Ultra-Compact Dwarf galaxies' (UCDs)
have been discovered in spectroscopic surveys of the Fornax galaxy cluster
by our team. UCDs have a special place in the fundamental plane of pressure
supported stellar systems. They are located at the high mass end of the
globular cluster (GC) distribution, reaching ~10^8 M_sun and obey a mass-size
relation unlike 'classical' GCs, but connecting to compact ellipticals.
Nowadays, dozens, if not hundreds, of UCDs and their fellow `dwarf galaxy
transition objects' (DGTOs), `giant globular clusters' (GGCs) and `extended
clusters' (ECs) have been identified in various environments, filling the
space in the fundamental plane between star clusters and dwarf galaxies.
I will review the knowledge we obtained over the last 16 years of these
sometimes still puzzling objects. I will present the occurence, spatial
distribution, dynamics and mass spectrum of UCDs in different environments.
For some of the bright UCDs, internal properties (metallicity, ages,
[alpha/Fe] abundances, internal kinematics, clues to their IMF, etc.) are
available, which I will highlight. Finally, I will summarize our current
ideas about their formation and will conclude that the majority of UCDs
belong to the 'star cluster family'.