CfA Colloquium: December 19, 2002

Speaker: Juliane Dalcanton (U. Washington)

Title: The Skinny on Galaxy Formation from Edge-On Disks

Abstract: Evidence within the Milky Way suggests that the early evolution of disk galaxies was complex, leaving behind faint stellar components as a fossil record. Unfortunately, these revealing features are extremely low surface brightness and have proven difficult to detect outside of the Milky Way. I will discuss new work showing that the previously elusive thick disk population is in fact pervasive, suggesting that thick disk formation is a generic feature of disk galaxy evolution. I also will show that the thick disk is the dominant stellar population in low mass galaxies. I will discuss the resulting constraints on galaxy formation models.