Speaker
Description
I will present our work on measuring the Milky Way (MW)’s halo edges and modeling the tidal stripping of satellite galaxies, addressing two key aspects of halo dynamics and boundaries: (1) halo growth and (2) environmental effects, respectively.
(1) Using the kinematics of nearby dwarf galaxies within 3 Mpc, we measured the depletion radius and the turnaround radius of the MW, along with their enclosed masses. The depletion radius separates a growing halo from the draining environment, while the turnaround radius marks the outer edge of the infalling region, quantifying the ongoing evolution of the MW outer halo.
(2) We developed the first general analytic model that incorporates tidal truncation and the subsequent re-virialization via violent relaxation. This model accurately reproduces the density profiles and tidal edges of simulated galaxies. We demonstrate that dark matter-deficient galaxies may form due to the differential tidal loss of dark matter and stars, with applications to ultra-diffuse galaxies both within and beyond the MW.
