Upper Limit on the Milky Way Mass from the Orbit of the Sagittarius Dwarf Satellite

Abstract

As one of the most massive Milky Way satellites, the Sagittarius dwarf galaxy has 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 Milky Way and Sagittarius by modeling the full infall of the satellite. We constrain the mass of the Galaxy based on the observed orbital parameters and multiple tidal streams of Sagittarius. Our semi-analytic modeling of the orbital dynamics agrees with full $N$-body simulations, and favors low values for the Milky Way mass, $\lesssim 10^{12}{M}_{\odot }$. This conclusion eases the tension between $\Lambda$CDM and the observed parameters of the Milky Way satellites.

Accepted by ApJ; 11 pages

References in corpus (18)

• Too big to fail? The puzzling darkness of massive Milky Way subhaloes
• The Milky Way's Circular Velocity Curve to 60 kpc and an Estimate of the Dark Matter Halo Mass from Kinematics of ~2400 SDSS Blue Horizontal Branch Stars
• Are the Magellanic Clouds on their First Passage about the Milky Way?
• The Milky Way's circular velocity curve between 4 and 14 kpc from APOGEE data
• A universal model for halo concentrations
• "Skinny Milky Way, Please", says Sagittarius
• The Origin of the Bifurcation in the Sagittarius Stream
• The nucleus of the Sagittarius dSph galaxy and M54: a window on the process of galaxy nucleation
• A Magellanic Origin of the DES Dwarfs
• Organized Chaos: Scatter in the relation between stellar mass and halo mass in small galaxies
• Shaken and Stirred: The Milky Way's Dark Substructures
• A Tail of Two Populations: Chemo-dynamics of the Sagittarius Stream and Implications for its Original Mass
• On the Run: mapping the escape speed across the Galaxy with SDSS
• Predicted Extension of the Sagittarius Stream to the Milky Way Virial Radius
• Distance to the Sagittarius Dwarf Galaxy using MACHO Project RR Lyrae stars
• Signatures of the M31-M32 Galactic Collision
• The connection between the host halo and the satellite galaxies of the Milky Way
• A dynamics-free lower bound on the mass of our galaxy

Cited by in corpus (31)

• Origin of the system of globular clusters in the Milky Way
• The Influence of Sagittarius and the Large Magellanic Cloud on the Milky Way Galaxy
• Reverse engineering the Milky Way
• From galactic bars to the Hubble tension: weighing up the astrophysical evidence for Milgromian gravity
• The origin of the Gaia phase-plane spiral
• The mass of our Milky Way
• The information content in cold stellar streams
• The Dragonfly Wide Field Survey. I. Telescope, Survey Design and Data Characterization
• The Sagittarius dwarf galaxy: Where did all the gas go?
• Dynamical Histories of the Crater II and Hercules Dwarf Galaxies
• Connecting the Milky Way potential profile to the orbital timescales and spatial structure of the Sagittarius Stream
• Satellites of Milky Way- and M31-like galaxies with TNG50: quenched fractions, gas content, and star formation histories
• The Magellanic System: the puzzle of the leading gas stream
• Determination of the escape velocity of the Milky Way using a proper motion selected halo sample
• Substructure at High Speed II: The Local Escape Velocity and Milky Way Mass with Gaia DR2
• The effect of Large Magellanic Cloud on the satellite galaxy population in Milky Way analogous Galaxies
• Tidally induced morphology of M33 in hydrodynamical simulations of its recent interaction with M31
• A Lower Limit on the Mass of Our Galaxy from the H3 Survey
• Physical characterization of recently discovered globular clusters in the Sagittarius dwarf spheroidal galaxy II. Metallicities, ages and luminosities
• The Smith Cloud: surviving a high speed transit of the Galactic disc
• The metallicity distribution in the core of the Sagittarus dwarf spheroidal: minimising the metallicity biases
• Detecting the Figure Rotation of Dark Matter Halos with Tidal Streams
• The Escape Velocity Profile of the Milky Way from Gaia DR3
• Globular Clusters Lost by the Sagittarius Dwarf Spheroidal Galaxy
• No globular cluster progenitors in Milky Way satellite galaxies
• An Orbit Fit to Likely Hermus Stream Stars
• Orbital phase-driven biases in Galactic mass constraints from stellar streams
• Fitting the density substructure of the stellar halo with MilkyWay@home
• Inferring the density and membership of stellar streams with flexible models: The GD-1 stream in Gaia Data Release 3
• One Stream or Two -- Exploring Andromeda's North West Stream
• Resolving local and global kinematic signatures of satellite mergers with billion particle simulations