Hyunsu Kong, UT-Austin

"Evolution of dark substructures in Milky-Way-mass dark matter halos"

Abstract: One of the key predictions of the ΛCDM cosmological model is the existence (and survival) of structure across an enormous range of scales, including below the scale at which we think galaxies can form. The Milky Way is no exception: it likely contains hundreds of very low-luminosity galaxies that are dominated by dark matter, as well as yet-undetected subhalos that are completely dark. Modeling the gravitational interaction between these subhalos and visible structures can provide an insight into understanding the physical nature of dark matter. In this talk, I will discuss predictions for the evolution of substructure within Milky-Way-mass dark matter halos. I will show the importance of modeling the Milky Way galaxy itself when making predictions, as subhalos in these simulations undergo more drastic tidal disruption than those in the dark-matter-only simulations. Using the results from the Phat ELVIS suite of cosmological simulations with and without embedded galaxy potentials, I will discuss the details of the evolutions in the properties of subhalos subjected to such tidally disrupting events. In addition, I will conclude with discussions on using my work to constrain dark matter models in relation to phenomena such as lensing, interaction with stellar streams, and the survivability of the lowest-mass galaxies.