Extragalactic Star Clusters and the Assembly Histories of Galaxies

I will report on the latest results from the SLUGGS imaging and spectroscopic survey of early type galaxies whose overarching goal is to unravel the formation histories of galaxies using the numbers, spatial distributions, stellar populations and kinematics of globular clusters to infer fundamental properties of their host galaxies. I will explore the connections between globular clusters and ultra compact dwarfs and how they can help us understand both the assembly histories of normal early type galaxies as well as the nature of ultra diffuse galaxies (UDGs). UDGs have the sizes of giant galaxies (>1.5 kpc) but the luminosities of dwarfs. The various UDG origin theories under debate separate broadly into two classes: giant galaxies that failed to form enough stars or dwarf galaxies that were puffed up in size.  The extremely low surface brightness of UDGs makes observations extremely challenging.  However, many, but not all, UDGs are overabundant in star clusters and the properties of these relatively bright “beacons” provide key insights into UDG formation.

Cody Hall, AB 107, University of Toronto

Jean Brodie. UC Santa Cruz

October 16, 2019
3:00 pm - 4:00 pm