제목: Ultra-Diffuse Galaxies - their properties and formation mechanisms
초록:
Ultra-diffuse galaxies (UDGs) are unusual populations, having very low surface brightness comparable to classical dwarf galaxies but much larger effective radius. After the discovery of several tens of UDGs in the Coma cluster, these faint stellar systems have been found in other clusters as well as groups and fields. I will present our observational studies for UDGs, mostly in the cluster environments. Our results show diversities of UDGs including globular cluster (GC) properties, their morphologies, and dynamical masses, although UDGs have higher mean GC specific frequency and more massive mean dynamical masses than those of classical dwarf galaxies. We also found the environmental dependence of UDG properties. I will discuss the implications of these results for UDG formation mechanisms.
