Title: Dynamics of the Milky Way Halo and Dark-Matter Deficient Galaxies

Speaker: Zhaozhou Li (The Hebrew University)

Time: 10:00am, December 26, 2023

Location: 5-516, PMO Xianlin Campus

Abstract: I will discuss two topics related to the dynamics of dark-matter (DM) halos.The mass distribution beyond 100 kpc of our Milky Way (MW) halo has historically been poorly constrained due to poor observations and model uncertainties. I will introduce two new efficient data-driven methods for dynamical modeling , which provide us with the current best estimates of the MW halo mass based on the motion of MW satellite galaxies.In the second part, I will address the puzzling dearth of DM in a fraction of dwarf and high-z massive galaxies that is not reproduced in current simulations. This discrepancy highlights our limited understanding of the halo/galaxy structural evolution. I will present a novel unified model for galaxy dynamical evolution driven by feedback outflows, mergers, and tidal interactions, and show how these processes can amplify structural diversity and create DM-deficient galaxies.