Poster Presentation

Dark matter distributions in the Galactic dwarf spheroidals

Author(s): Kohei Hayashi, Yutaka Hirai, Masashi Chiba, Tomoaki Ishiyama

Presenter: Kohei Hayashi (National Institute of Technology, Ichinoseki College)

Elucidating dark matter density profiles in the Galactic dwarf satellites is essential to understanding the nature of dark matter. In this work, we present the current constraints on dark matter densities in the dwarf spheroidal galaxies in the Milky Way. Applying our constructed non-spherical mass models to the currently available kinematic data of the satellites, we find that several ultra-faint dwarf galaxies favor cusped central profiles. We compare our results with the simulated subhalos on the plane between the dark matter density at 150pc and the pericenter distance. We find that the most observed satellites and the simulated subhalos are similarly distributed on this plane, except for Antlia2, Crater2, and Tucana3 which deviate considerably from the simulated ones. Despite considering tidal effects, the subhalos detected by commonly-used subhalo finders can be difficult to explain such a huge deviation.