2017/03/31 by M. Dierickx, Marion I. P. Dierickx, Abraham Loeb
Physics and Astronomy · #Astronomy #Astrophysics #Dwarf galaxy #Galactic halo #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gamma-ray bursts and supernovae #Halo #Milky Way #Physics #Sagittarius #Sagittarius A* #Satellite #Stellar, planetary, and galactic studies #astro-ph.GA
paper · pdf · doi:10.3847/1538-4357/aa8767
Accepted by ApJ; 11 pages
arxiv created 2017/09/15 · openalex publication_date 2017/09/20 · arxiv updated 2017/10/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Abstract As one of the most massive Milky Way (MW) satellites, the Sagittarius dwarf galaxy played an important role in shaping the Galactic disk and stellar halo morphologies. The disruption of Sagittarius over several close-in passages has populated the halo of our Galaxy with large-scale tidal streams and offers a unique diagnostic tool for measuring its gravitational potential. Here, we test different progenitor mass models for the MW and Sagittarius by modeling the full infall of the satellite. We constrain the mass of the Galaxy based on the kinematics of the satellite remnant and multiple tidal streams of Sagittarius. Our semianalytic modeling of the orbital dynamics agrees with full N -body simulations, and favors low values for the MW mass, . This conclusion eases the tension between ΛCDM and the observed parameters of the MW satellites.