New Insights into the Nature of the Galactic Halo

Speaker: Jesse Han (Harvard) In Person and zoom 

Zoom info: https://stanford.zoom.us/my/sihanyuan?pwd=QnpsUHZWWGJ2ekVYWmZVL3BmM0gzZz09

The Galactic halo holds clues to the assembly history of the Galaxy. I will present new discoveries about the 6D phase space distribution of stars in the Galactic halo, which in turn can constrain the underlying dark matter distribution. Based on these new insights, I offer a solution to the long-standing problem on the warp (and flare) of the Galactic disk. Furthermore, I show that the same dataset used to study the stellar halo can also be used to constrain the distribution of cold gas in the circum-galactic and interstellar medium. I will close the talk by introducing a future all-sky survey with Roman that can revolutionize studies of the Galactic halo, which can enable the discovery of dark matter substructures in our Galaxy.